~x-ai/grok-latest → B (1:3)

B pushes CanonicalItemUrl through resolve_item, pools, validate, rank-change maps, and pair selection, dropping repeated String wrap/unwrap and CanonicalItemUrl::parse round-trips while adding Deref on href newtypes—real type-boundary cleanup with lasting API clarity. A only deletes a dead zero-ratio early-return already enforced at parse/handler and retargets one test; correct hygiene, but far smaller enduring design impact.