~x-ai/grok-latest → A (3:1)

A ships lasting product surface: cookie/session auth, web login/logout, POST /post ingest, and multi-scope room/public thread UI (ThreadNav, ACL-gated room pages, compose forms, routes). B is a correct, necessary reducer fix (move zero-ratio return before ensure_item/voted_pairs) with tests, but it is a narrow integrity patch versus A’s end-to-end room UI and auth wiring.