NEO-146: apply C# collection and using style fixes

Replace .ToArray() with collection spread, simplify single-statement
await using blocks, use Lock for Postgres schema gates, and document
IDE0063/IDE0305/IDE0330/CA1859 conventions in csharp-style.md.

.cursor/rules/csharp-style.md

@@ -54,7 +54,61 @@ if (string.IsNullOrEmpty(key))
 - **File-scoped namespaces** (`namespace X;`) for new single-namespace files when the SDK/version allows.
 - **Pattern matching / nullability:** prefer modern C# features where they simplify code; honor **nullable reference type** annotations when the project enables them.
 
-## Members
+## Collection expressions (IDE0305)
+
+- Prefer **collection spread** (`[.. source]`) over **`.ToArray()`** / **`.ToList()`** when materializing a sequence into a new array or list for return values, record `with` copies, or local snapshots.
+- Give an **explicit target type** when the compiler cannot infer one (CS9176), e.g. `string[] ids = [.. query.Select(static x => x.Id)];`.
+- In **assertions**, avoid passing a bare spread directly to APIs with span overloads (e.g. `Assert.Equal`) — assign to a typed local first:
+
+```csharp
+// Prefer
+return [.. query];
+GrantedItems = [.. row.GrantedItems],
+
+// When type inference fails
+string[] expectedOrder = [.. registry.GetDefinitionsInIdOrder().Select(static d => d.Id)];
+string[] actualOrder = [.. body.Quests.Select(static row => row.QuestId)];
+Assert.Equal(expectedOrder, actualOrder);
+
+// Avoid (ambiguous Assert overloads; unnecessary allocation helper)
+Assert.Equal(expectedOrder, [.. body.Quests.Select(static row => row.QuestId)]);
+return query.ToArray();
+```
+
+## `using` / `await using` (IDE0063)
+
+- When a **`using` or `await using` block contains exactly one statement**, prefer the declaration form without braces: `await using var conn = …;` then the single statement on following lines **only if** it is still logically one resource scope (typical for `NpgsqlConnection` + one command in integration-test reset helpers).
+- **Keep braced `using (var …) { … }`** when the block has **multiple statements** (Arrange + Act + Assert inside one scope, seed loops, or any sequence that shares locals).
+- **Do not flatten** multi-statement blocks into `using var` at method scope when inner scopes reuse names like `store`, `registry`, or `scope` — that causes **CS0136** name clashes. Use distinct names (`seedStore`, `actScope`, `readStore`) or keep the braced block.
+
+```csharp
+// Prefer — single disposable, single follow-on statement
+await using var conn = new NpgsqlConnection(cs);
+await conn.OpenAsync();
+
+// Prefer — multiple statements in one scope
+using (var firstScope = Factory.Services.CreateScope())
+{
+    var store = firstScope.ServiceProvider.GetRequiredService<IExampleStore>();
+    Assert.True(store.TryAppend(row));
+}
+
+// Avoid — flattens to method scope and collides with a later `var store`
+using var firstScope = Factory.Services.CreateScope();
+var store = firstScope.ServiceProvider.GetRequiredService<IExampleStore>();
+Assert.True(store.TryAppend(row));
+// … later …
+var store = secondScope.ServiceProvider.GetRequiredService<IExampleStore>(); // CS0136
+```
+
+## Postgres schema gates (IDE0330)
+
+- In `*Bootstrap.cs` types, use **`System.Threading.Lock`** (not `object`) for static schema-initialization gates: `private static readonly Lock SchemaGate = new();`.
+
+## Concrete return types (CA1859)
+
+- When a private helper always returns a materialized array, prefer the **concrete array type** as the return type (e.g. `RewardItemGrantApplied[]`) instead of `IReadOnlyList<T>` if callers only need the array and analyzers suggest it.
+
 
 - Prefer **expression-bodied** members only when they stay one clear idea.
 - **LINQ:** favor readability over micro-chains; break complex queries across lines.

server/NeonSprawl.Server.Tests/Game/AbilityInput/HotbarLoadoutPersistenceIntegrationTests.cs

@@ -37,13 +37,12 @@ public sealed class HotbarLoadoutPersistenceIntegrationTests(PostgresIntegration
         HttpStatusCode postStatus;
 
         // Act
-        using (var firstClient = Factory.CreateClient())
+        using var firstClient = Factory.CreateClient();
-        {
         var post = await firstClient.PostAsJsonAsync(
             "/game/players/dev-local-1/hotbar-loadout",
             update);
         postStatus = post.StatusCode;
-        }
+
 
         // Assert
         await using var secondFactory = new PostgresWebApplicationFactory();
@@ -73,14 +72,10 @@ public sealed class HotbarLoadoutPersistenceIntegrationTests(PostgresIntegration
         var ddl = await File.ReadAllTextAsync(ddlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var apply = new NpgsqlCommand(ddl, conn))
+        await using var apply = new NpgsqlCommand(ddl, conn);
-        {
         await apply.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_hotbar_loadout;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_hotbar_loadout;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server.Tests/Game/Contracts/ContractInstancePersistenceIntegrationTests.cs

@@ -138,14 +138,12 @@ public sealed class ContractInstancePersistenceIntegrationTests(PostgresIntegrat
         }
 
         ContractInstanceState readBack;
-        await using (var secondFactory = new PostgresWebApplicationFactory())
+        await using var secondFactory = new PostgresWebApplicationFactory();
-        {
         using var secondScope = secondFactory.Services.CreateScope();
-            var store = secondScope.ServiceProvider.GetRequiredService<IContractInstanceStore>();
+        var readStore = secondScope.ServiceProvider.GetRequiredService<IContractInstanceStore>();
-            readBack = store.TryGet(PlayerId, InstanceId, out var snapshot)
+        readBack = readStore.TryGet(PlayerId, InstanceId, out var snapshot)
             ? snapshot
             : null!;
-        }
 
         // Assert
         Assert.NotNull(readBack);
@@ -176,21 +174,15 @@ public sealed class ContractInstancePersistenceIntegrationTests(PostgresIntegrat
         var instanceDdl = await File.ReadAllTextAsync(instanceDdlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var applyPosition = new NpgsqlCommand(positionDdl, conn))
+        await using var applyPosition = new NpgsqlCommand(positionDdl, conn);
-        {
         await applyPosition.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
 
-        await using (var applyInstance = new NpgsqlCommand(instanceDdl, conn))
+        await using var applyInstance = new NpgsqlCommand(instanceDdl, conn);
-        {
         await applyInstance.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server.Tests/Game/Contracts/ContractOutcomePersistenceIntegrationTests.cs

@@ -54,14 +54,12 @@ public sealed class ContractOutcomePersistenceIntegrationTests(PostgresIntegrati
         }
 
         ContractOutcomeRow readBack;
-        await using (var secondFactory = new PostgresWebApplicationFactory())
+        await using var secondFactory = new PostgresWebApplicationFactory();
-        {
         using var secondScope = secondFactory.Services.CreateScope();
-            var outcomeStore = secondScope.ServiceProvider.GetRequiredService<IContractOutcomeStore>();
+        var readOutcomeStore = secondScope.ServiceProvider.GetRequiredService<IContractOutcomeStore>();
-            readBack = outcomeStore.TryGetByIdempotencyKey(idempotencyKey, out var row)
+        readBack = readOutcomeStore.TryGetByIdempotencyKey(idempotencyKey, out var row)
             ? row
             : null!;
-        }
 
         // Assert
         Assert.NotNull(readBack);
@@ -125,11 +123,10 @@ public sealed class ContractOutcomePersistenceIntegrationTests(PostgresIntegrati
             RecordedAt);
         // Act
         bool appended;
-        using (var scope = Factory.Services.CreateScope())
+        using var scope = Factory.Services.CreateScope();
-        {
         var outcomeStore = scope.ServiceProvider.GetRequiredService<IContractOutcomeStore>();
         appended = outcomeStore.TryAppend(outcomeRow);
-        }
+
         // Assert
         Assert.False(appended);
     }
@@ -158,26 +155,18 @@ public sealed class ContractOutcomePersistenceIntegrationTests(PostgresIntegrati
         var outcomeDdl = await File.ReadAllTextAsync(outcomeDdlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var applyPosition = new NpgsqlCommand(positionDdl, conn))
+        await using var applyPosition = new NpgsqlCommand(positionDdl, conn);
-        {
         await applyPosition.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
 
-        await using (var applyInstance = new NpgsqlCommand(instanceDdl, conn))
+        await using var applyInstance = new NpgsqlCommand(instanceDdl, conn);
-        {
         await applyInstance.ExecuteNonQueryAsync();
-        }
 
-        await using (var applyOutcome = new NpgsqlCommand(outcomeDdl, conn))
+        await using var applyOutcome = new NpgsqlCommand(outcomeDdl, conn);
-        {
         await applyOutcome.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server.Tests/Game/Factions/FactionStandingPersistenceIntegrationTests.cs

@@ -31,12 +31,10 @@ public sealed class FactionStandingPersistenceIntegrationTests(PostgresIntegrati
         }
 
         FactionStandingReadOutcome readBack;
-        await using (var secondFactory = new PostgresWebApplicationFactory())
+        await using var secondFactory = new PostgresWebApplicationFactory();
-        {
         using var secondScope = secondFactory.Services.CreateScope();
-            var store = secondScope.ServiceProvider.GetRequiredService<IFactionStandingStore>();
+        var readStore = secondScope.ServiceProvider.GetRequiredService<IFactionStandingStore>();
-            readBack = store.TryGetStanding(PlayerId, GridFactionId);
+        readBack = readStore.TryGetStanding(PlayerId, GridFactionId);
-        }
 
         // Assert
         Assert.True(writeOutcome.Success);
@@ -69,11 +67,10 @@ public sealed class FactionStandingPersistenceIntegrationTests(PostgresIntegrati
 
         // Act
         FactionStandingReadOutcome readBack;
-        using (var scope = Factory.Services.CreateScope())
+        using var scope = Factory.Services.CreateScope();
-        {
         var store = scope.ServiceProvider.GetRequiredService<IFactionStandingStore>();
         readBack = store.TryGetStanding(PlayerId, GridFactionId);
-        }
+
 
         // Assert
         Assert.True(readBack.Success);
@@ -102,21 +99,15 @@ public sealed class FactionStandingPersistenceIntegrationTests(PostgresIntegrati
         var standingDdl = await File.ReadAllTextAsync(standingDdlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var applyPosition = new NpgsqlCommand(positionDdl, conn))
+        await using var applyPosition = new NpgsqlCommand(positionDdl, conn);
-        {
         await applyPosition.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
 
-        await using (var applyStanding = new NpgsqlCommand(standingDdl, conn))
+        await using var applyStanding = new NpgsqlCommand(standingDdl, conn);
-        {
         await applyStanding.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server.Tests/Game/Factions/InMemoryReputationDeltaStoreTests.cs

@@ -85,7 +85,7 @@ public sealed class InMemoryReputationDeltaStoreTests
         // Act
         var rows = store.GetDeltasForPlayer(PlayerId);
         // Assert
-        Assert.Equal(["delta-a", "delta-m", "delta-z"], rows.Select(static r => r.Id).ToArray());
+        Assert.Equal(["delta-a", "delta-m", "delta-z"], [.. rows.Select(static r => r.Id)]);
     }
 
     [Fact]

server/NeonSprawl.Server.Tests/Game/Factions/ReputationDeltaPersistenceIntegrationTests.cs

@@ -40,12 +40,10 @@ public sealed class ReputationDeltaPersistenceIntegrationTests(PostgresIntegrati
         }
 
         IReadOnlyList<ReputationDeltaRow> readBack;
-        await using (var secondFactory = new PostgresWebApplicationFactory())
+        await using var secondFactory = new PostgresWebApplicationFactory();
-        {
         using var secondScope = secondFactory.Services.CreateScope();
-            var store = secondScope.ServiceProvider.GetRequiredService<IReputationDeltaStore>();
+        var readStore = secondScope.ServiceProvider.GetRequiredService<IReputationDeltaStore>();
-            readBack = store.GetDeltasForPlayer(PlayerId);
+        readBack = readStore.GetDeltasForPlayer(PlayerId);
-        }
 
         // Assert
         var persisted = Assert.Single(readBack);
@@ -77,21 +75,15 @@ public sealed class ReputationDeltaPersistenceIntegrationTests(PostgresIntegrati
         var auditDdl = await File.ReadAllTextAsync(auditDdlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var applyPosition = new NpgsqlCommand(positionDdl, conn))
+        await using var applyPosition = new NpgsqlCommand(positionDdl, conn);
-        {
         await applyPosition.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
 
-        await using (var applyAudit = new NpgsqlCommand(auditDdl, conn))
+        await using var applyAudit = new NpgsqlCommand(auditDdl, conn);
-        {
         await applyAudit.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server.Tests/Game/Gathering/ResourceNodeInstancePersistenceIntegrationTests.cs

@@ -48,11 +48,11 @@ public sealed class ResourceNodeInstancePersistenceIntegrationTests(PostgresInte
         await ResetInstanceTableAsync();
         using (var seedScope = Factory.Services.CreateScope())
         {
-            var registry = seedScope.ServiceProvider.GetRequiredService<IResourceNodeDefinitionRegistry>();
+            var seedRegistry = seedScope.ServiceProvider.GetRequiredService<IResourceNodeDefinitionRegistry>();
-            var store = seedScope.ServiceProvider.GetRequiredService<IResourceNodeInstanceStore>();
+            var seedStore = seedScope.ServiceProvider.GetRequiredService<IResourceNodeInstanceStore>();
             for (var i = 0; i < 10; i++)
             {
-                _ = ResourceNodeInstanceOperations.TryCommitSuccessfulGatherDecrement(AlphaId, registry, store);
+                _ = ResourceNodeInstanceOperations.TryCommitSuccessfulGatherDecrement(AlphaId, seedRegistry, seedStore);
             }
         }
 
@@ -60,13 +60,11 @@ public sealed class ResourceNodeInstancePersistenceIntegrationTests(PostgresInte
         ResourceNodeInstanceMutationOutcome denyOutcome;
         ResourceNodeInstanceSnapshot persisted;
         await using var secondFactory = new PostgresWebApplicationFactory();
-        using (var scope = secondFactory.Services.CreateScope())
+        using var actScope = secondFactory.Services.CreateScope();
-        {
+        var actRegistry = actScope.ServiceProvider.GetRequiredService<IResourceNodeDefinitionRegistry>();
-            var registry = scope.ServiceProvider.GetRequiredService<IResourceNodeDefinitionRegistry>();
+        var actStore = actScope.ServiceProvider.GetRequiredService<IResourceNodeInstanceStore>();
-            var store = scope.ServiceProvider.GetRequiredService<IResourceNodeInstanceStore>();
+        denyOutcome = ResourceNodeInstanceOperations.TryCommitSuccessfulGatherDecrement(AlphaId, actRegistry, actStore);
-            denyOutcome = ResourceNodeInstanceOperations.TryCommitSuccessfulGatherDecrement(AlphaId, registry, store);
+        actStore.TryGetRemainingGathers(AlphaId, out persisted);
-            store.TryGetRemainingGathers(AlphaId, out persisted);
-        }
 
         // Assert
         Assert.Equal(ResourceNodeInstanceMutationKind.Denied, denyOutcome.Kind);
@@ -92,14 +90,10 @@ public sealed class ResourceNodeInstancePersistenceIntegrationTests(PostgresInte
         var ddl = await File.ReadAllTextAsync(ddlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var apply = new NpgsqlCommand(ddl, conn))
+        await using var apply = new NpgsqlCommand(ddl, conn);
-        {
         await apply.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE resource_node_instance;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE resource_node_instance;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server.Tests/Game/Gigs/GigProgressionGrantPersistenceIntegrationTests.cs

@@ -97,26 +97,18 @@ public sealed class GigProgressionGrantPersistenceIntegrationTests(PostgresInteg
         var gigDdl = await File.ReadAllTextAsync(gigDdlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var applyPosition = new NpgsqlCommand(positionDdl, conn))
+        await using var applyPosition = new NpgsqlCommand(positionDdl, conn);
-        {
         await applyPosition.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
 
-        await using (var applyGig = new NpgsqlCommand(gigDdl, conn))
+        await using var applyGig = new NpgsqlCommand(gigDdl, conn);
-        {
         await applyGig.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncateGig = new NpgsqlCommand("TRUNCATE player_gig_progression;", conn))
+        await using var truncateGig = new NpgsqlCommand("TRUNCATE player_gig_progression;", conn);
-        {
         await truncateGig.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server.Tests/Game/Items/PlayerInventoryPersistenceIntegrationTests.cs

@@ -54,31 +54,31 @@ public sealed class PlayerInventoryPersistenceIntegrationTests(PostgresIntegrati
         await ResetInventoryTableAsync();
         using (var seedScope = Factory.Services.CreateScope())
         {
-            var registry = seedScope.ServiceProvider.GetRequiredService<IItemDefinitionRegistry>();
+            var seedRegistry = seedScope.ServiceProvider.GetRequiredService<IItemDefinitionRegistry>();
-            var store = seedScope.ServiceProvider.GetRequiredService<IPlayerInventoryStore>();
+            var seedStore = seedScope.ServiceProvider.GetRequiredService<IPlayerInventoryStore>();
             for (var i = 0; i < PlayerInventorySnapshot.BagSlotCount; i++)
             {
                 _ = PlayerInventoryOperations.TryAddStack(
                     "dev-local-1",
                     "survey_drone_kit",
                     quantity: 1,
-                    registry,
+                    seedRegistry,
-                    store);
+                    seedStore);
             }
         }
 
         // Act
         PlayerInventoryMutationOutcome denyOutcome;
-        using (var scope = Factory.Services.CreateScope())
+        using (var actScope = Factory.Services.CreateScope())
         {
-            var registry = scope.ServiceProvider.GetRequiredService<IItemDefinitionRegistry>();
+            var actRegistry = actScope.ServiceProvider.GetRequiredService<IItemDefinitionRegistry>();
-            var store = scope.ServiceProvider.GetRequiredService<IPlayerInventoryStore>();
+            var actStore = actScope.ServiceProvider.GetRequiredService<IPlayerInventoryStore>();
             denyOutcome = PlayerInventoryOperations.TryAddStack(
                 "dev-local-1",
                 "scrap_metal_bulk",
                 quantity: 1,
-                registry,
+                actRegistry,
-                store);
+                actStore);
         }
 
         // Act — verify on fresh host
@@ -120,28 +120,20 @@ public sealed class PlayerInventoryPersistenceIntegrationTests(PostgresIntegrati
         var inventoryDdl = await File.ReadAllTextAsync(inventoryDdlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var applyPosition = new NpgsqlCommand(positionDdl, conn))
+        await using var applyPosition = new NpgsqlCommand(positionDdl, conn);
-        {
         await applyPosition.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
 
-        await using (var applyInventory = new NpgsqlCommand(inventoryDdl, conn))
+        await using var applyInventory = new NpgsqlCommand(inventoryDdl, conn);
-        {
         await applyInventory.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncateInventory = new NpgsqlCommand("TRUNCATE player_inventory;", conn))
+        await using var truncateInventory = new NpgsqlCommand("TRUNCATE player_inventory;", conn);
-        {
         await truncateInventory.ExecuteNonQueryAsync();
     }
-    }
 
     private static int OccupiedBagSlotCount(PlayerInventorySnapshot snapshot)
     {

server/NeonSprawl.Server.Tests/Game/Mastery/MasteryCatalogRegistryTests.cs

@@ -89,7 +89,7 @@ public class MasteryCatalogRegistryTests
         // Act
         var tracks = registry.GetTracksInSkillIdOrder();
         // Assert
-        Assert.Equal(["intrusion", "refine", "salvage"], tracks.Select(t => t.SkillId).ToArray());
+        Assert.Equal(["intrusion", "refine", "salvage"], [.. tracks.Select(t => t.SkillId)]);
     }
 
     [Fact]
@@ -111,7 +111,7 @@ public class MasteryCatalogRegistryTests
         // Act
         var ordered = registry.GetPerksInIdOrder();
         // Assert
-        Assert.Equal(["a_perk", "m_perk", "z_perk"], ordered.Select(p => p.Id).ToArray());
+        Assert.Equal(["a_perk", "m_perk", "z_perk"], [.. ordered.Select(p => p.Id)]);
     }
 
     [Fact]

server/NeonSprawl.Server.Tests/Game/Mastery/PerkStateApiTests.cs

@@ -158,10 +158,9 @@ public sealed class PerkStateApiTests
         // Assert
         Assert.Equal(HttpStatusCode.OK, post.StatusCode);
         var json = await post.Content.ReadAsStringAsync();
-        using (var doc = JsonDocument.Parse(json))
+        using var doc = JsonDocument.Parse(json);
-        {
         Assert.False(doc.RootElement.TryGetProperty("reasonCode", out _));
-        }
+
 
         var envelope = JsonSerializer.Deserialize<PerkBranchSelectResponse>(json);
         Assert.NotNull(envelope);

server/NeonSprawl.Server.Tests/Game/Mastery/PerkStatePersistenceIntegrationTests.cs

@@ -20,23 +20,20 @@ public sealed class PerkStatePersistenceIntegrationTests(PostgresIntegrationHarn
         // Arrange
         await ResetPerkTablesAsync();
         const string playerId = "dev-local-1";
-        using (var scope = Factory.Services.CreateScope())
+        using var scope = Factory.Services.CreateScope();
-        {
         var xpStore = scope.ServiceProvider.GetRequiredService<IPlayerSkillProgressionStore>();
         var engine = scope.ServiceProvider.GetRequiredService<PerkUnlockEngine>();
         Assert.True(xpStore.TryApplyXpDelta(playerId, "salvage", 450, out _, out _));
         Assert.True(engine.TrySelectBranch(playerId, "salvage", 1, "scrap_efficiency").Success);
         _ = engine.ReevaluateAfterLevelUp(playerId, "salvage", newLevel: 4);
-        }
+
 
         // Act
         PerkStateSnapshot snapshot;
-        await using (var secondFactory = new PostgresWebApplicationFactory())
+        await using var secondFactory = new PostgresWebApplicationFactory();
-        {
+        using var secondScope = secondFactory.Services.CreateScope();
-            using var scope = secondFactory.Services.CreateScope();
+        var perkStore = secondScope.ServiceProvider.GetRequiredService<IPlayerPerkStateStore>();
-            var perkStore = scope.ServiceProvider.GetRequiredService<IPlayerPerkStateStore>();
         snapshot = perkStore.GetSnapshot(playerId);
-        }
 
         // Assert
         Assert.Equal("scrap_efficiency", snapshot.BranchPicksBySkillId["salvage"][1]);
@@ -65,21 +62,15 @@ public sealed class PerkStatePersistenceIntegrationTests(PostgresIntegrationHarn
         var perkDdl = await File.ReadAllTextAsync(perkDdlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var applyPosition = new NpgsqlCommand(positionDdl, conn))
+        await using var applyPosition = new NpgsqlCommand(positionDdl, conn);
-        {
         await applyPosition.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
 
-        await using (var applyPerk = new NpgsqlCommand(perkDdl, conn))
+        await using var applyPerk = new NpgsqlCommand(perkDdl, conn);
-        {
         await applyPerk.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server.Tests/Game/PositionState/PostgresPositionStateIntegrationTests.cs

@@ -62,12 +62,11 @@ public sealed class PostgresPositionStateIntegrationTests(PostgresIntegrationHar
         PositionStateResponse? persisted = null;
 
         // Act
-        using (var first = Factory.CreateClient())
+        using var first = Factory.CreateClient();
-        {
         var post = await first.PostAsJsonAsync("/game/players/dev-local-1/move", cmd);
         postStatus = post.StatusCode;
         persisted = await post.Content.ReadFromJsonAsync<PositionStateResponse>();
-        }
+
 
         // Assert
         await using var secondFactory = new PostgresWebApplicationFactory();
@@ -122,15 +121,11 @@ public sealed class PostgresPositionStateIntegrationTests(PostgresIntegrationHar
         var ddl = await File.ReadAllTextAsync(ddlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var apply = new NpgsqlCommand(ddl, conn))
+        await using var apply = new NpgsqlCommand(ddl, conn);
-        {
         await apply.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
     }

server/NeonSprawl.Server.Tests/Game/Quests/PlayerQuestProgressPersistenceIntegrationTests.cs

@@ -70,17 +70,15 @@ public sealed class PlayerQuestProgressPersistenceIntegrationTests(PostgresInteg
 
         // Act — read back through a fresh host
         QuestStepState readBack;
-        await using (var secondFactory = new PostgresWebApplicationFactory())
+        await using var secondFactory = new PostgresWebApplicationFactory();
-        {
         using var secondScope = secondFactory.Services.CreateScope();
-            var store = secondScope.ServiceProvider.GetRequiredService<IPlayerQuestStateStore>();
+        var readStore = secondScope.ServiceProvider.GetRequiredService<IPlayerQuestStateStore>();
-            readBack = store.TryGetProgress(
+        readBack = readStore.TryGetProgress(
             PlayerId,
             PrototypeE7M1QuestCatalogRules.GatherIntroQuestId,
             out var snapshot)
             ? snapshot
             : null!;
-        }
 
         // Assert
         Assert.NotNull(readBack);
@@ -108,12 +106,10 @@ public sealed class PlayerQuestProgressPersistenceIntegrationTests(PostgresInteg
         }
 
         var readBackExists = false;
-        await using (var secondFactory = new PostgresWebApplicationFactory())
+        await using var secondFactory = new PostgresWebApplicationFactory();
-        {
         using var secondScope = secondFactory.Services.CreateScope();
-            var store = secondScope.ServiceProvider.GetRequiredService<IPlayerQuestStateStore>();
+        var readStore = secondScope.ServiceProvider.GetRequiredService<IPlayerQuestStateStore>();
-            readBackExists = store.TryGetProgress(PlayerId, questId, out _);
+        readBackExists = readStore.TryGetProgress(PlayerId, questId, out _);
-        }
 
         // Assert
         Assert.False(readBackExists);
@@ -141,21 +137,15 @@ public sealed class PlayerQuestProgressPersistenceIntegrationTests(PostgresInteg
         var questDdl = await File.ReadAllTextAsync(questDdlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var applyPosition = new NpgsqlCommand(positionDdl, conn))
+        await using var applyPosition = new NpgsqlCommand(positionDdl, conn);
-        {
         await applyPosition.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
 
-        await using (var applyQuest = new NpgsqlCommand(questDdl, conn))
+        await using var applyQuest = new NpgsqlCommand(questDdl, conn);
-        {
         await applyQuest.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server.Tests/Game/Quests/QuestDefinitionsWorldApiTests.cs

@@ -24,8 +24,8 @@ public class QuestDefinitionsWorldApiTests
         Assert.NotNull(body.Quests);
         Assert.Equal(PrototypeE7M1QuestCatalogRules.ExpectedQuestIds.Count, body.Quests.Count);
         Assert.Equal(
-            PrototypeE7M1QuestCatalogRules.ExpectedQuestIds.Order(StringComparer.Ordinal).ToArray(),
+            [.. PrototypeE7M1QuestCatalogRules.ExpectedQuestIds.Order(StringComparer.Ordinal)],
-            body.Quests.Select(q => q.Id).ToArray());
+            [.. body.Quests.Select(q => q.Id)]);
 
         var gatherIntro = body.Quests.Single(q => q.Id == "prototype_quest_gather_intro");
         Assert.Equal("Intro: Salvage Run", gatherIntro.DisplayName);

server/NeonSprawl.Server.Tests/Game/Quests/QuestProgressApiTests.cs

@@ -63,7 +63,7 @@ public sealed class QuestProgressApiTests
         await using var factory = new InMemoryWebApplicationFactory();
         var client = factory.CreateClient();
         var registry = factory.Services.GetRequiredService<IQuestDefinitionRegistry>();
-        var expectedQuestOrder = registry.GetDefinitionsInIdOrder().Select(static d => d.Id).ToArray();
+        string[] expectedQuestOrder = [.. registry.GetDefinitionsInIdOrder().Select(static d => d.Id)];
 
         // Act
         var response = await client.GetAsync($"/game/players/{PlayerId}/quest-progress");
@@ -75,7 +75,8 @@ public sealed class QuestProgressApiTests
         Assert.Equal(QuestProgressListResponse.CurrentSchemaVersion, body!.SchemaVersion);
         Assert.Equal(PlayerId, body.PlayerId);
         Assert.Equal(expectedQuestOrder.Length, body.Quests.Count);
-        Assert.Equal(expectedQuestOrder, body.Quests.Select(static row => row.QuestId).ToArray());
+        string[] actualQuestOrder = [.. body.Quests.Select(static row => row.QuestId)];
+        Assert.Equal(expectedQuestOrder, actualQuestOrder);
         foreach (var row in body.Quests)
         {
             Assert.Equal(QuestProgressApi.StatusNotStarted, row.Status);

server/NeonSprawl.Server.Tests/Game/Skills/SkillProgressionGrantPersistenceIntegrationTests.cs

@@ -29,12 +29,11 @@ public sealed class SkillProgressionGrantPersistenceIntegrationTests(PostgresInt
         HttpResponseMessage postResponse;
 
         // Act — write grant through first host
-        using (var firstClient = Factory.CreateClient())
+        using var firstClient = Factory.CreateClient();
-        {
         postResponse = await firstClient.PostAsJsonAsync(
             "/game/players/dev-local-1/skill-progression",
             grant);
-        }
+
 
         // Act — read back through a fresh host (forces DB round-trip / new DI scope)
         await using var secondFactory = new PostgresWebApplicationFactory();
@@ -78,26 +77,18 @@ public sealed class SkillProgressionGrantPersistenceIntegrationTests(PostgresInt
         var progressionDdl = await File.ReadAllTextAsync(progressionDdlPath);
         await using var conn = new NpgsqlConnection(cs);
         await conn.OpenAsync();
-        await using (var applyPosition = new NpgsqlCommand(positionDdl, conn))
+        await using var applyPosition = new NpgsqlCommand(positionDdl, conn);
-        {
         await applyPosition.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn))
+        await using var truncate = new NpgsqlCommand("TRUNCATE player_position CASCADE;", conn);
-        {
         await truncate.ExecuteNonQueryAsync();
-        }
 
         PostgresPositionBootstrap.SeedDevPlayer(conn, options);
 
-        await using (var applyProgression = new NpgsqlCommand(progressionDdl, conn))
+        await using var applyProgression = new NpgsqlCommand(progressionDdl, conn);
-        {
         await applyProgression.ExecuteNonQueryAsync();
-        }
 
-        await using (var truncateProgression = new NpgsqlCommand("TRUNCATE player_skill_progression;", conn))
+        await using var truncateProgression = new NpgsqlCommand("TRUNCATE player_skill_progression;", conn);
-        {
         await truncateProgression.ExecuteNonQueryAsync();
     }
-    }
 }

server/NeonSprawl.Server/Game/AbilityInput/PostgresHotbarLoadoutBootstrap.cs

@@ -1,10 +1,12 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.AbilityInput;
 
 /// <summary>Applies NEO-29 hotbar loadout table DDL once per process.</summary>
 public static class PostgresHotbarLoadoutBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V002__player_hotbar_loadout.sql");
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
     private static int _schemaReady;
 
     public static void EnsureSchema(Npgsql.NpgsqlDataSource dataSource)

server/NeonSprawl.Server/Game/Combat/AbilityDefinitionCatalogLoader.cs

@@ -26,9 +26,8 @@ public static class AbilityDefinitionCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(abilitiesDirectory, "*_abilities.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(abilitiesDirectory, "*_abilities.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_abilities.json files under {abilitiesDirectory}");
 

server/NeonSprawl.Server/Game/Combat/AbilityDefinitionRegistry.cs

@@ -43,7 +43,7 @@ public sealed class AbilityDefinitionRegistry(AbilityDefinitionCatalog catalog)
 
     private static IReadOnlyList<AbilityDefRow> BuildDefinitionsInIdOrder(AbilityDefinitionCatalog catalog)
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<AbilityDefRow>(ids.Length);
         foreach (var id in ids)
         {

server/NeonSprawl.Server/Game/Contracts/ContractTemplateCatalogLoader.cs

@@ -62,9 +62,8 @@ public static class ContractTemplateCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(contractsDirectory, "*_contract_templates.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(contractsDirectory, "*_contract_templates.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_contract_templates.json files under {contractsDirectory}");
 

server/NeonSprawl.Server/Game/Contracts/ContractTemplateRegistry.cs

@@ -27,7 +27,7 @@ public sealed class ContractTemplateRegistry(ContractTemplateCatalog catalog) :
     /// <inheritdoc />
     public IReadOnlyList<ContractTemplateRow> GetDefinitionsInIdOrder()
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<ContractTemplateRow>(ids.Length);
         foreach (var id in ids)
             list.Add(catalog.ById[id]);

server/NeonSprawl.Server/Game/Contracts/InMemoryContractOutcomeStore.cs

@@ -73,7 +73,7 @@ public sealed class InMemoryContractOutcomeStore : IContractOutcomeStore
             query = query.Take(limit.Value);
         }
 
-        return query.ToArray();
+        return [..query];
     }
 
     /// <inheritdoc />
@@ -85,10 +85,9 @@ public sealed class InMemoryContractOutcomeStore : IContractOutcomeStore
             return false;
         }
 
-        var idsToRemove = rowsById.Values
+        string[] idsToRemove = [.. rowsById.Values
             .Where(row => string.Equals(row.ContractInstanceId, instanceId, StringComparison.Ordinal))
-            .Select(static row => row.Id)
+            .Select(static row => row.Id)];
-            .ToArray();
 
         foreach (var id in idsToRemove)
         {
@@ -124,9 +123,9 @@ public sealed class InMemoryContractOutcomeStore : IContractOutcomeStore
             PlayerId = playerId,
             ContractInstanceId = instanceId,
             IdempotencyKey = idempotencyKey,
-            GrantedItems = row.GrantedItems.ToArray(),
+            GrantedItems = [..row.GrantedItems],
-            GrantedSkillXp = row.GrantedSkillXp.ToArray(),
+            GrantedSkillXp = [..row.GrantedSkillXp],
-            GrantedReputation = row.GrantedReputation.ToArray(),
+            GrantedReputation = [..row.GrantedReputation],
         };
         return true;
     }

server/NeonSprawl.Server/Game/Contracts/PostgresContractInstanceBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Contracts;
 
 /// <summary>Applies NEO-146 contract instance table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresContractInstanceBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V011__contract_instance.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Contracts/PostgresContractOutcomeBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Contracts;
 
 /// <summary>Applies NEO-146 contract outcome table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresContractOutcomeBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V012__contract_outcome.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Contracts/PostgresContractOutcomeStore.cs

@@ -162,19 +162,19 @@ public sealed class PostgresContractOutcomeStore(Npgsql.NpgsqlDataSource dataSou
     private static string SerializeGrants<T>(IReadOnlyList<T> grants) =>
         JsonSerializer.Serialize(grants, JsonOptions);
 
-    private static IReadOnlyList<RewardItemGrantApplied> DeserializeItems(string json)
+    private static RewardItemGrantApplied[] DeserializeItems(string json)
     {
         var parsed = JsonSerializer.Deserialize<RewardItemGrantApplied[]>(json, JsonOptions);
         return parsed ?? [];
     }
 
-    private static IReadOnlyList<RewardSkillXpGrantApplied> DeserializeSkillXp(string json)
+    private static RewardSkillXpGrantApplied[] DeserializeSkillXp(string json)
     {
         var parsed = JsonSerializer.Deserialize<RewardSkillXpGrantApplied[]>(json, JsonOptions);
         return parsed ?? [];
     }
 
-    private static IReadOnlyList<RewardReputationGrantApplied> DeserializeReputation(string json)
+    private static RewardReputationGrantApplied[] DeserializeReputation(string json)
     {
         var parsed = JsonSerializer.Deserialize<RewardReputationGrantApplied[]>(json, JsonOptions);
         return parsed ?? [];
@@ -201,9 +201,9 @@ public sealed class PostgresContractOutcomeStore(Npgsql.NpgsqlDataSource dataSou
             PlayerId = playerId,
             ContractInstanceId = instanceId,
             IdempotencyKey = idempotencyKey,
-            GrantedItems = row.GrantedItems.ToArray(),
+            GrantedItems = [..row.GrantedItems],
-            GrantedSkillXp = row.GrantedSkillXp.ToArray(),
+            GrantedSkillXp = [..row.GrantedSkillXp],
-            GrantedReputation = row.GrantedReputation.ToArray(),
+            GrantedReputation = [..row.GrantedReputation],
         };
         return true;
     }

server/NeonSprawl.Server/Game/Crafting/RecipeDefinitionCatalogLoader.cs

@@ -36,9 +36,8 @@ public static class RecipeDefinitionCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(recipesDirectory, "*_recipes.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(recipesDirectory, "*_recipes.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_recipes.json files under {recipesDirectory}");
 

server/NeonSprawl.Server/Game/Crafting/RecipeDefinitionRegistry.cs

@@ -24,7 +24,7 @@ public sealed class RecipeDefinitionRegistry(RecipeDefinitionCatalog catalog) :
 
     private static IReadOnlyList<RecipeDefRow> BuildDefinitionsInIdOrder(RecipeDefinitionCatalog catalog)
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<RecipeDefRow>(ids.Length);
         foreach (var id in ids)
         {

server/NeonSprawl.Server/Game/Encounters/EncounterDefinitionCatalogLoader.cs

@@ -30,9 +30,8 @@ public static class EncounterDefinitionCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(encountersDirectory, "*_encounters.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(encountersDirectory, "*_encounters.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_encounters.json files under {encountersDirectory}");
 

server/NeonSprawl.Server/Game/Encounters/EncounterDefinitionRegistry.cs

@@ -43,7 +43,7 @@ public sealed class EncounterDefinitionRegistry(EncounterDefinitionCatalog catal
 
     private static IReadOnlyList<EncounterDefRow> BuildDefinitionsInIdOrder(EncounterDefinitionCatalog catalog)
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<EncounterDefRow>(ids.Length);
         foreach (var id in ids)
         {

server/NeonSprawl.Server/Game/Encounters/InMemoryEncounterCompleteEventStore.cs

@@ -27,7 +27,7 @@ public sealed class InMemoryEncounterCompleteEventStore : IEncounterCompleteEven
 
             eventsByKey[key] = completeEvent with
             {
-                GrantedItems = completeEvent.GrantedItems.ToArray(),
+                GrantedItems = [..completeEvent.GrantedItems],
             };
             return true;
         }

server/NeonSprawl.Server/Game/Encounters/RewardTableDefinitionCatalogLoader.cs

@@ -35,9 +35,8 @@ public static class RewardTableDefinitionCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(rewardTablesDirectory, "*_reward_tables.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(rewardTablesDirectory, "*_reward_tables.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_reward_tables.json files under {rewardTablesDirectory}");
 

server/NeonSprawl.Server/Game/Encounters/RewardTableDefinitionRegistry.cs

@@ -43,7 +43,7 @@ public sealed class RewardTableDefinitionRegistry(RewardTableDefinitionCatalog c
 
     private static IReadOnlyList<RewardTableDefRow> BuildDefinitionsInIdOrder(RewardTableDefinitionCatalog catalog)
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<RewardTableDefRow>(ids.Length);
         foreach (var id in ids)
         {

server/NeonSprawl.Server/Game/Factions/FactionDefinitionCatalogLoader.cs

@@ -26,9 +26,8 @@ public static class FactionDefinitionCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(factionsDirectory, "*_factions.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(factionsDirectory, "*_factions.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_factions.json files under {factionsDirectory}");
 

server/NeonSprawl.Server/Game/Factions/FactionDefinitionRegistry.cs

@@ -27,7 +27,7 @@ public sealed class FactionDefinitionRegistry(FactionDefinitionCatalog catalog)
     /// <inheritdoc />
     public IReadOnlyList<FactionDefRow> GetDefinitionsInIdOrder()
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<FactionDefRow>(ids.Length);
         foreach (var id in ids)
         {

server/NeonSprawl.Server/Game/Factions/InMemoryReputationDeltaStore.cs

@@ -58,7 +58,7 @@ public sealed class InMemoryReputationDeltaStore : IReputationDeltaStore
             query = query.Take(limit.Value);
         }
 
-        return query.ToArray();
+        return [..query];
     }
 
     /// <inheritdoc />
@@ -71,13 +71,12 @@ public sealed class InMemoryReputationDeltaStore : IReputationDeltaStore
             return false;
         }
 
-        var idsToRemove = rowsById.Values
+        string[] idsToRemove = [.. rowsById.Values
             .Where(row =>
                 string.Equals(row.PlayerId, player, StringComparison.Ordinal) &&
                 string.Equals(row.SourceKind, ReputationDeltaSourceKinds.QuestCompletion, StringComparison.Ordinal) &&
                 string.Equals(row.SourceId, sourceId, StringComparison.Ordinal))
-            .Select(static row => row.Id)
+            .Select(static row => row.Id)];
-            .ToArray();
 
         foreach (var id in idsToRemove)
         {

server/NeonSprawl.Server/Game/Factions/PostgresPlayerFactionStandingBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Factions;
 
 /// <summary>Applies NEO-135 faction standing table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresPlayerFactionStandingBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V009__player_faction_standing.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Factions/PostgresReputationDeltaBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Factions;
 
 /// <summary>Applies NEO-135 reputation delta audit table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresReputationDeltaBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V010__reputation_delta_audit.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Gathering/PostgresResourceNodeInstanceBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Gathering;
 
 /// <summary>Applies NEO-61 resource-node instance table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresResourceNodeInstanceBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V006__resource_node_instance.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Gathering/ResourceNodeCatalogLoader.cs

@@ -35,15 +35,13 @@ public static class ResourceNodeCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var nodeJsonFiles = Directory.GetFiles(resourceNodesDirectory, "*_resource_nodes.json", SearchOption.TopDirectoryOnly)
+        string[] nodeJsonFiles = [.. Directory.GetFiles(resourceNodesDirectory, "*_resource_nodes.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+            .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (nodeJsonFiles.Length == 0)
             errors.Add($"error: no *_resource_nodes.json files under {resourceNodesDirectory}");
 
-        var yieldJsonFiles = Directory.GetFiles(resourceNodesDirectory, "*_resource_yields.json", SearchOption.TopDirectoryOnly)
+        string[] yieldJsonFiles = [.. Directory.GetFiles(resourceNodesDirectory, "*_resource_yields.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+            .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (yieldJsonFiles.Length == 0)
             errors.Add($"error: no *_resource_yields.json files under {resourceNodesDirectory}");
 

server/NeonSprawl.Server/Game/Gigs/PostgresGigProgressionBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Gigs;
 
 /// <summary>Applies NEO-44 gig progression table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresGigProgressionBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V007__player_gig_progression.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Items/ItemDefinitionCatalogLoader.cs

@@ -26,9 +26,8 @@ public static class ItemDefinitionCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(itemsDirectory, "*_items.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(itemsDirectory, "*_items.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_items.json files under {itemsDirectory}");
 

server/NeonSprawl.Server/Game/Items/ItemDefinitionRegistry.cs

@@ -27,7 +27,7 @@ public sealed class ItemDefinitionRegistry(ItemDefinitionCatalog catalog) : IIte
     /// <inheritdoc />
     public IReadOnlyList<ItemDefRow> GetDefinitionsInIdOrder()
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<ItemDefRow>(ids.Length);
         foreach (var id in ids)
         {

server/NeonSprawl.Server/Game/Items/PostgresPlayerInventoryBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Items;
 
 /// <summary>Applies NEO-54 inventory table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresPlayerInventoryBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V005__player_inventory.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Mastery/MasteryCatalogLoader.cs

@@ -29,9 +29,8 @@ public static class MasteryCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(masteryDirectory, "*_mastery.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(masteryDirectory, "*_mastery.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_mastery.json files under {masteryDirectory}");
 

server/NeonSprawl.Server/Game/Mastery/PostgresPerkStateBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Mastery;
 
 /// <summary>Applies NEO-47 perk state table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresPerkStateBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V004__player_perk_state.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Npc/NpcBehaviorDefinitionCatalogLoader.cs

@@ -26,9 +26,8 @@ public static class NpcBehaviorDefinitionCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(npcBehaviorsDirectory, "*_npc_behaviors.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(npcBehaviorsDirectory, "*_npc_behaviors.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_npc_behaviors.json files under {npcBehaviorsDirectory}");
 

server/NeonSprawl.Server/Game/Npc/NpcBehaviorDefinitionRegistry.cs

@@ -43,7 +43,7 @@ public sealed class NpcBehaviorDefinitionRegistry(NpcBehaviorDefinitionCatalog c
 
     private static IReadOnlyList<NpcBehaviorDefRow> BuildDefinitionsInIdOrder(NpcBehaviorDefinitionCatalog catalog)
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<NpcBehaviorDefRow>(ids.Length);
         foreach (var id in ids)
         {

server/NeonSprawl.Server/Game/PositionState/PostgresPositionBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.PositionState;
 
 /// <summary>
@@ -8,7 +10,7 @@ public static class PostgresPositionBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V001__player_position.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
     private static int _schemaReady;
 
     /// <summary>
@@ -36,10 +38,9 @@ public static class PostgresPositionBootstrap
 
             var ddl = File.ReadAllText(ddlPath);
             using var conn = dataSource.OpenConnection();
-            using (var cmd = new Npgsql.NpgsqlCommand(ddl, conn))
+            using var cmd = new Npgsql.NpgsqlCommand(ddl, conn);
-            {
             cmd.ExecuteNonQuery();
-            }
+
 
             System.Threading.Volatile.Write(ref _schemaReady, 1);
         }

server/NeonSprawl.Server/Game/Quests/PostgresPlayerQuestProgressBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Quests;
 
 /// <summary>Applies NEO-116 quest progress table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresPlayerQuestProgressBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V008__player_quest_progress.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Quests/PrototypeE7M2QuestCatalogRules.cs

@@ -126,14 +126,12 @@ public static class PrototypeE7M2QuestCatalogRules
 
     private static NormalizedBundle NormalizeBundle(QuestRewardBundleRow bundle) =>
         new(
-            bundle.ItemGrants
+            [.. bundle.ItemGrants
                 .OrderBy(g => g.ItemId, StringComparer.Ordinal)
-                .ThenBy(g => g.Quantity)
+                .ThenBy(g => g.Quantity)],
-                .ToArray(),
+            [.. bundle.SkillXpGrants
-            bundle.SkillXpGrants
                 .OrderBy(g => g.SkillId, StringComparer.Ordinal)
-                .ThenBy(g => g.Amount)
+                .ThenBy(g => g.Amount)]);
-                .ToArray());
 
     private static bool BundlesEqual(NormalizedBundle left, NormalizedBundle right)
     {

server/NeonSprawl.Server/Game/Quests/PrototypeE7M3QuestFactionRules.cs

@@ -161,18 +161,15 @@ public static class PrototypeE7M3QuestFactionRules
 
     private static NormalizedBundle NormalizeBundle(QuestRewardBundleRow bundle) =>
         new(
-            bundle.ItemGrants
+            [.. bundle.ItemGrants
                 .OrderBy(g => g.ItemId, StringComparer.Ordinal)
-                .ThenBy(g => g.Quantity)
+                .ThenBy(g => g.Quantity)],
-                .ToArray(),
+            [.. bundle.SkillXpGrants
-            bundle.SkillXpGrants
                 .OrderBy(g => g.SkillId, StringComparer.Ordinal)
-                .ThenBy(g => g.Amount)
+                .ThenBy(g => g.Amount)],
-                .ToArray(),
+            [.. bundle.ReputationGrants
-            bundle.ReputationGrants
                 .OrderBy(g => g.FactionId, StringComparer.Ordinal)
-                .ThenBy(g => g.Amount)
+                .ThenBy(g => g.Amount)]);
-                .ToArray());
 
     private static bool BundlesEqual(NormalizedBundle left, NormalizedBundle right)
     {

server/NeonSprawl.Server/Game/Quests/QuestDefinitionCatalogLoader.cs

@@ -64,9 +64,8 @@ public static class QuestDefinitionCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(questsDirectory, "*_quests.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(questsDirectory, "*_quests.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_quests.json files under {questsDirectory}");
 

server/NeonSprawl.Server/Game/Quests/QuestDefinitionRegistry.cs

@@ -43,7 +43,7 @@ public sealed class QuestDefinitionRegistry(QuestDefinitionCatalog catalog) : IQ
 
     private static IReadOnlyList<QuestDefRow> BuildDefinitionsInIdOrder(QuestDefinitionCatalog catalog)
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<QuestDefRow>(ids.Length);
         foreach (var id in ids)
         {

server/NeonSprawl.Server/Game/Rewards/InMemoryRewardDeliveryStore.cs

@@ -27,9 +27,9 @@ public sealed class InMemoryRewardDeliveryStore : IRewardDeliveryStore
 
             eventsByKey[key] = deliveryEvent with
             {
-                GrantedItems = deliveryEvent.GrantedItems.ToArray(),
+                GrantedItems = [..deliveryEvent.GrantedItems],
-                GrantedSkillXp = deliveryEvent.GrantedSkillXp.ToArray(),
+                GrantedSkillXp = [..deliveryEvent.GrantedSkillXp],
-                GrantedReputation = deliveryEvent.GrantedReputation.ToArray(),
+                GrantedReputation = [..deliveryEvent.GrantedReputation],
             };
             return true;
         }

server/NeonSprawl.Server/Game/Skills/PostgresSkillProgressionBootstrap.cs

@@ -1,3 +1,5 @@
+using System.Threading;
+
 namespace NeonSprawl.Server.Game.Skills;
 
 /// <summary>Applies NEO-38 skill progression table DDL once per process.</summary>
@@ -5,7 +7,7 @@ public static class PostgresSkillProgressionBootstrap
 {
     private static readonly string DdlRelativePath = Path.Combine("db", "migrations", "V003__player_skill_progression.sql");
 
-    private static readonly object SchemaGate = new();
+    private static readonly Lock SchemaGate = new();
 
     private static int _schemaReady;
 

server/NeonSprawl.Server/Game/Skills/SkillDefinitionCatalogLoader.cs

@@ -26,9 +26,8 @@ public static class SkillDefinitionCatalogLoader
         if (errors.Count > 0)
             ThrowIfAny(errors);
 
-        var jsonFiles = Directory.GetFiles(skillsDirectory, "*_skills.json", SearchOption.TopDirectoryOnly)
+        string[] jsonFiles = [.. Directory.GetFiles(skillsDirectory, "*_skills.json", SearchOption.TopDirectoryOnly)
-            .OrderBy(p => p, StringComparer.Ordinal)
+                .OrderBy(p => p, StringComparer.Ordinal)];
-            .ToArray();
         if (jsonFiles.Length == 0)
             errors.Add($"error: no *_skills.json files under {skillsDirectory}");
 

server/NeonSprawl.Server/Game/Skills/SkillDefinitionRegistry.cs

@@ -27,7 +27,7 @@ public sealed class SkillDefinitionRegistry(SkillDefinitionCatalog catalog) : IS
     /// <inheritdoc />
     public IReadOnlyList<SkillDefRow> GetDefinitionsInIdOrder()
     {
-        var ids = catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal).ToArray();
+        string[] ids = [.. catalog.ById.Keys.OrderBy(k => k, StringComparer.Ordinal)];
         var list = new List<SkillDefRow>(ids.Length);
         foreach (var id in ids)
         {