~anthropic/claude-sonnet-latest → A (8:2)

Side A is a substantial architectural migration (converting the entire REST API surface to a batched RPC model, room/thread scoping refactor, reducer state redesign, and extensive test rewrites) that establishes the foundation the rest of the codebase builds on. Side B is a small incremental feature (RoomList command) built entirely on top of A's RPC infrastructure, useful but narrow in scope and lasting impact by comparison.