~x-ai/grok-latest → B (1:35)

Commit B introduces a real lasting design: ItemId becomes full canonical URLs, extracts composable url_rules (engine + per-domain registry for Reddit/YouTube normalization, breadcrumbs, parents), and updates path_types, reddit mapping, projection, and tests accordingly. Commit A is a one-line UI tweak swapping a disabled span for an a href="#" in the forum paginator with no design or bugfix impact.