~x-ai/grok-latest → B (2:5)

B replaces flat string scopes with a real hierarchical domain model (ItemId parent/breadcrumbs, GlobalTree/NodeState, journaled NodeEnsured, tree-scoped votes and UI), which changes how rankings and navigation work permanently. A is a strong hygiene refactor—moving canonicalize_* and CanonicalItemUrl into slug-types and wrapping wire hrefs as GardenItemUrl/ForumThreadUrl—but it mostly relocates and type-wraps existing URL rules without introducing comparable new behavior.