~x-ai/grok-latest → A (2:1)

A fixes real import behavior by replacing link_child/ensure_path with apply_entity_under_parent so Reddit listings attach under the subreddit without pulling /comments/ path segments, and makes unranked children show entity titles via child_label plus tighter SSE/children integration tests. B mostly relocates existing canonicalization and URL helpers into slug-types (GardenItemUrl/ForumThreadUrl re-exports) with call-site renames—useful structure, but little new lasting behavior versus A’s functional tree and UI correctness fixes.