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

Side A fixes a real, concrete bug: nested RwLock reads across match arms that would deadlock the RoomCreate/RoomGrant RPC paths (tokio::sync::RwLock is not reentrant), and backs it with a new integration test plus fixes to flaky/deadlock-prone test infra (log-file redirection, HTTP timeouts) and incorrect test assertions. Side B is a broad but mostly mechanical refactor (renaming from_storage_str->from_stored, threading CanonicalItemUrl/newtype Deref impls through many call sites) that improves type-safety but doesn't fix an active defect, making it closer to structural churn than a critical correctness fix.