feat: face-frame hosting for roof wall children + items on roof walls

Wall-mounted items join doors/windows on roof-segment wall faces, and
the storage model moves to FACE-LOCAL coordinates so hosted children
track segment edits live.

- Children store roofFace + position [u, v, z-from-mid-plane] with
  rotation 0 in-frame — the exact wall-child conventions (the wall
  volume's mid-plane lands on the nominal footprint). A shared
  <RoofFaceHostFrame> derives segment pose + face frame from the
  live-override-merged segment: children follow resize handle drags in
  real time and never jump on commit. No re-anchor cascade needed —
  position is authoritative, the frame is derived. migrateNodes
  converts branch-era segment-local data.
- Items: roofWallStrategy + roof:* handlers in the placement
  coordinator (surface 'roof-wall'), Shift free-place normalized with
  walls, ItemSystem wall-side push extended to segment hosts, correct
  2D plan glyphs via face→segment→roof pose composition. The roof
  hit resolver + overlap guard moved to @pascal-app/editor (the
  coordinator lives there; nodes already depends on editor).
- Cuts: subtractAccessoryCuts extracted and applied in BOTH the
  merged-shell and per-segment CSG paths (full edit mode / painted
  segments used to lose every hole), built from the CURRENT host
  geometry and live-effective children so holes follow segment and
  opening drags.
- Handle rig: the grandparent portal now maps the node's world pose
  into the portal frame instead of composing parent+node registry
  poses — correct for any nesting (the face-frame group broke the
  old assumption), identical for walls.
- Host-field hygiene: useDraftNode.commit/adopt and the window panel
  duplicate forward roofSegmentId/roofFace/wallId; every roof↔wall
  re-anchor clears and every revert restores them.

Codex-reviewed (design consultation, adversarial rounds on the
replaced cascade and on this refactor); frame conventions locked by
unit tests. Record: private-editor plans/editor-roof-wall-openings.md.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

packages/nodes/src/window/definition.ts

@@ -161,7 +161,7 @@ export const windowDefinition: NodeDefinition<typeof WindowNode> = {
     },
     // `wallId` / `roofSegmentId` are re-derived from the surface under
     // the cursor at preset placement time — see door for the pattern.
-    hostRefFields: ['wallId', 'roofSegmentId'],
+    hostRefFields: ['wallId', 'roofSegmentId', 'roofFace'],
   },
 
   parametrics: windowParametrics,