~x-ai/grok-latest → A (3:1)

A delivers lasting infrastructure: server-side theme cookies with POST /theme, auth cookie re-issue so login does not drop theme, layout/CSS integration, plus item_path_for_api_in_room/forum_thread_web_url and RPC/next-hint wiring so private rooms emit correct /r/… ontology and thread URLs (with tests). B is valuable but narrower—out-of-band WEB_BROWSER_AGENT delegate, drop the all-items next-pair fallback, remove swap, and rename /vote/compare→/vote—real fixes, but less project surface than A’s combined theme + room wire-path work.