~x-ai/grok-latest → A (2:1)

A fixes real import semantics: children attach via apply_entity_under_parent (entity data + direct parent link without ensure_path pulling /comments/ segments) and ranking_panel/child_label show imported titles, with expanded SSE/integration coverage. B is useful UX/consistency cleanup (SSR home compose slot, delete ExpandNewThreadForm + toolbar) but mainly removes a redundant morph path rather than correcting core data wiring.