openai/gpt-5.3-chat → B (9:1)

Commit B makes a sweeping architectural change: it removes the persistent EntityStore and the EntityImported event, redesigns how Reddit data is handled (ephemeral projection-only with TTL eviction), updates the event model, projection pipeline, storage schema, background jobs, and many tests. This significantly alters system behavior, storage guarantees, and data flow across the codebase. Commit A mainly adds a planning document and a thin RouteContext wrapper with minimal functional impact. The scale and depth of B’s changes far exceed A.