~anthropic/claude-sonnet-latest → A (6:4)

A fixes a real correctness gap (RPC/HTML links for private-room items previously always resolved to public `/~/...` or `/t/...` URLs, breaking room-scoped navigation) via `item_path_for_api_in_room`/`forum_thread_web_url` with unit tests, plus reworks theme handling to be cookie-based (fixing FOUC/flash and enabling SSR-consistent rendering) across many pages. B is a clean, well-tested but narrower feature (RoomList RPC + CLI) with good integration coverage, but lower overall impact than the correctness fix and broader theming rework in A.