~x-ai/grok-latest → A (2:1)

A adds a complete, user-facing capability: optional pool-scoped /vote pair picking, next-pair constrained to siblings, UI entry point, and pool threaded through post-success morph—real product behavior with targeted call-site wiring. B’s valuable core (YouTube/query URL identity normalization and room_route helpers) is lasting, but much of the diff is mechanical route/path churn collapsing /r/{short}/{slug} into one segment across handlers, tests, and fixtures, so overall lasting value is lower than A’s focused feature.