~x-ai/grok-latest → A (3:1)

A replaces the ad-hoc ParsedUrl combinator stack (engine.rs + host-specific normalize_* paths) with a graph/DFA-based canonicalization API, which is a lasting redesign of core ItemId URL identity. B only changes sibling nav grouping so each unranked item is its own group, plus one regression test—useful but localized UI behavior versus foundational URL rules.