Apply Roslyn/dotnet-format fixes across NeonSprawl.Server and
NeonSprawl.Server.Tests: collection expressions, concrete helper
return types, record XML docs, logging guards, quest store refactors,
and removal of redundant usings via GlobalUsings.cs. Extend
csharp-style.md with the recurring patterns.
In-memory IEncounterProgressStore and IEncounterCompletionStore with
EncounterProgressOperations for activation, defeat tracking, and
all-targets-defeated checks; unit tests and docs.
VinPropane