Add QuestObjectiveWiring with auto step advance/complete, hook into
GatherOperations, CraftOperations, EncounterCompletionOperations, and
QuestStateOperations accept/advance for inventory_has_item checks.
Add IEncounterCompleteEventStore with in-memory implementation, record
events on successful TryCompleteAndGrant, and expand reward_delivery
hook comments for future QuestRewardBundle routing.