Merge origin/main into feat/placement-interaction-overhaul

Resolve 7 conflicts keeping our snapping migration + floorplan perf work as
source of truth, combined with main's MEP run-continuation / Alt-detach /
latch handles. Rebuilt two import blocks the auto-merge silently truncated
(node-arrow-handles.tsx, duct-fitting/move-tool.tsx).

Verified: tsc clean across core/viewer/editor/nodes/mcp, 451 tests pass,
biome clean. Floorplan view-transform re-render storm confirmed pre-existing
(not introduced by this merge).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/nodes/src/door/preview.tsx

@@ -29,7 +29,7 @@ const DoorPreview = ({
     const m = buildDoorPreviewMesh(node)
     m.layers.set(EDITOR_LAYER)
     return m
-  }, [node.width, node.height, node.frameDepth, node.openingShape, node.doorType, node.leafCount])
+  }, [node])
 
   // Ghost treatment (clone + tint + raycast-off) re-applies if the tint flips;
   // its cleanup only disposes the clones it made.