Move: pure imperative via sceneRegistry (smooth, zero re-renders); drop dev logs

User feedback: updating the store per tick caused tons of React
re-renders → laggy drag. Switched to pure imperative.

MoveRegistryNodeTool now:
- Mutates `sceneRegistry.nodes.get(id).position` directly per
  grid:move tick. No useScene.updateNode during drag. No store
  change → no renderer re-render → R3F doesn't reapply
  `position={node.position}` → the imperative mutation sticks.
- On commit: single tracked `useScene.updateNode(id, { position })`.
  Undo replays one step (original → final), no per-tick spam.
- On cancel / unmount: imperatively snap the mesh back to original.
  Store was never touched so no data revert needed.

Trade-off vs the items pattern (which does update the store per tick
and re-renders per tick): our approach is faster but assumes the
renderer doesn't re-render mid-drag. Items get away with constant
re-renders because their renderer is heavily optimized; for parametric
shelves (and future kinds) the imperative path is simpler and faster.

Cleanup: removed the dev `[shelf] rendered` and `[shelf] placed`
console.info logs from the shelf renderer and tool. They were Phase 2
verification scaffolding — no longer needed now that everything works.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/nodes/src/shelf/tool.tsx

@@ -75,8 +75,6 @@ const ShelfTool = () => {
       useScene.getState().createNode(shelf, activeLevelId)
       useViewer.getState().setSelection({ selectedIds: [shelf.id] })
       triggerSFX('sfx:structure-build')
-      // biome-ignore lint/suspicious/noConsole: dev-only verification log
-      console.info('[shelf] placed', shelf.id, 'level-local', position, 'parent', activeLevelId)
     }
 
     emitter.on('grid:move', onGridMove)