~anthropic/claude-sonnet-latest → B (55:45)

B fixes a real, subtle production bug (a tokio RwLock read-guard held across the match arm causing potential deadlock in RoomGrant/RoomCreate), adds a regression test, and hardens test infra (timeouts, log-file redirection to avoid pipe deadlocks) — genuine correctness and reliability value. A is a large but reasonable simplification (dropping an over-engineered graph parser for a simpler URL parser), which is good cleanup but mostly deletes unused complexity rather than fixing a live bug, and removes test tooling (Playwright browser test) without clear justification beyond simplification.