openai/gpt-chat-latest → B (3:2)

Side B performs a broad architectural refactor by moving canonicalization and path/URL identity into a shared `slug_types::paths` module, replacing ad hoc string helpers with strongly typed `GardenItemUrl`, `ForumThreadUrl`, and related types across RPCs, validation, and API responses. Side A adds a useful `RoomList` RPC, CLI subcommand, and thorough integration tests for per-user room visibility, but it is a localized feature, whereas Side B establishes reusable infrastructure that reduces duplication and makes path handling consistent project-wide.