~x-ai/grok-latest → A (4:1)

Commit A lands the core ItemId redesign (new item_id/item_wire modules, removal of CanonicalItemUrl, and propagation through reducer, ranking, RPC, and HTML), a lasting domain-model improvement. Commit B only repairs OAuth/Reddit test mocks and a few Playwright helpers (query split, getRequestBody, redirect length, null-safe token/state), which restores E2E auth but is narrower test-infrastructure value.