feat(export): baked GLB export with identity, clips, cutout fix (phases 0-1)

Promote the client GLB export into the baked-artifact format from
plans/editor-baked-glb-export.md (phases 0 and 1).

- NodeMaterial -> classic MeshStandardMaterial conversion at export. The
  viewer's MeshStandard/LambertNodeMaterial set isNodeMaterial, not
  isMeshStandardMaterial, so GLTFExporter would otherwise drop every
  surface to a blank default. KTX2 (compressed) maps are decompressed via
  WebGPUTextureUtils so the exporter can embed them (PNG for now; KTX2
  re-encode is deferred to the phase-3 bake worker).
- Identity stamping from sceneRegistry: node.name = pascalId and
  extras = { pascalId, kind, label?, openable?, clips? }; all other
  userData stripped so editor/runtime ephemera never reach glTF extras.
- Door/window open clips baked from the build-once + pose-at-t primitives
  (door pascalSwingLeaf marker, window poseWindowMovingParts). Clips named
  by label ("Door 1: open"), carry extras.loop = false (consumers play
  once and hold; dumb glTF players still loop).
- Cutout fix: door/window selection hitboxes hide via material.visible,
  which onlyVisible misses, so the hitbox box plugged the wall opening.
  Non-renderable container meshes now keep their node but lose geometry;
  childless ones are removed.
- Editor-overlay stripping mirrors the thumbnail capture: emit
  thumbnail:before/after-capture so scene-layer affordances (handles,
  ceiling/site brackets) self-hide, and drop anything off SCENE_LAYER
  (gizmos, grid, zone fills).

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

packages/viewer/src/index.ts

@@ -157,6 +157,9 @@ export { getVisibleWallMaterials } from './systems/wall/wall-materials'
 // 800+ lines of CSG / mitering logic during Phase 3. These exports are
 // removed in Phase 6 when the legacy mount points are deleted.
 export { WallSystem } from './systems/wall/wall-system'
-export { WindowAnimationSystem } from './systems/window/window-animation-system'
+export {
+  poseWindowMovingParts,
+  WindowAnimationSystem,
+} from './systems/window/window-animation-system'
 export { buildWindowPreviewMesh, WindowSystem } from './systems/window/window-system'
 export { ZoneSystem } from './systems/zone/zone-system'

packages/viewer/src/systems/door/door-system.tsx

@@ -1092,6 +1092,7 @@ function addDoorLeaf(
     hingeX,
     hingeSide,
     swingRotation,
+    openRotationY,
     segments,
     contentPadding,
     handle,
@@ -1117,6 +1118,10 @@ function addDoorLeaf(
     hingeX: number
     hingeSide: 'left' | 'right'
     swingRotation: number
+    // Leaf rotation (radians, about the hinge Y axis) at fully-open. The GLB
+    // exporter reads this off the leaf group to bake an open/close clip; it is
+    // the kinematic endpoint, independent of the current `swingRotation`.
+    openRotationY: number
     segments: DoorNode['segments']
     contentPadding: DoorNode['contentPadding']
     handle: boolean
@@ -1147,6 +1152,10 @@ function addDoorLeaf(
   const leafGroup = new THREE.Group()
   leafGroup.position.set(hingeX, 0, 0)
   leafGroup.rotation.y = swingRotation
+  // Marks this group as the swing leaf and records its fully-open angle so the
+  // GLB exporter can bake an open/close animation clip from a single pose. The
+  // exporter strips this marker before writing the file.
+  leafGroup.userData.pascalSwingLeaf = { axis: 'y', openRotationY }
   mesh.add(leafGroup)
 
   const addLeafBox = (
@@ -2461,6 +2470,7 @@ function updateDoorMesh(rawNode: DoorNode, mesh: THREE.Mesh) {
       hingeX: -insideWidth / 2,
       hingeSide: 'left',
       swingRotation: -clampedSwingAngle * swingDirectionSign,
+      openRotationY: (-Math.PI / 2) * swingDirectionSign,
       segments,
       contentPadding,
       handle,
@@ -2489,6 +2499,7 @@ function updateDoorMesh(rawNode: DoorNode, mesh: THREE.Mesh) {
       hingeX: insideWidth / 2,
       hingeSide: 'right',
       swingRotation: clampedSwingAngle * swingDirectionSign,
+      openRotationY: (Math.PI / 2) * swingDirectionSign,
       segments,
       contentPadding,
       handle,
@@ -2520,6 +2531,7 @@ function updateDoorMesh(rawNode: DoorNode, mesh: THREE.Mesh) {
       hingeX,
       hingeSide: hingesSide,
       swingRotation: clampedSwingAngle * swingDirectionSign * hingeDirectionSign,
+      openRotationY: (Math.PI / 2) * swingDirectionSign * hingeDirectionSign,
       segments,
       contentPadding,
       handle,

packages/viewer/src/systems/window/window-animation-system.tsx

@@ -7,6 +7,7 @@ import {
   type WindowNode,
 } from '@pascal-app/core'
 import { useFrame } from '@react-three/fiber'
+import type { Object3D } from 'three'
 import {
   AWNING_WINDOW_SASH_NAME,
   CASEMENT_WINDOW_SASH_NAME,
@@ -28,12 +29,20 @@ function markWindowDirty(windowId: AnyNodeId) {
   scene.dirtyNodes.add(windowId)
 }
 
-function applyDirectWindowAnimation(windowId: AnyNodeId, value: number) {
-  const node = useScene.getState().nodes[windowId]
-  if (node?.type !== 'window') return false
-
-  const mesh = sceneRegistry.nodes.get(windowId)
-
+/**
+ * Pose a window's moving parts (sash/panel/slats) at `value` (0 = closed,
+ * 1 = open) by mutating the named child groups under `mesh`. Returns true when
+ * the window type has a direct pose path and the named parts were found.
+ *
+ * This is the single source of truth for window kinematics: the live animation
+ * system poses the registered scene mesh, and the GLB exporter poses an export
+ * clone to sample the open/close keyframes for a baked animation clip.
+ */
+export function poseWindowMovingParts(
+  node: WindowNode,
+  mesh: Object3D | undefined,
+  value: number,
+): boolean {
   if (node.windowType === 'sliding') {
     const activePanel = mesh?.getObjectByName(SLIDING_WINDOW_ACTIVE_PANEL_NAME)
     if (!activePanel) return false
@@ -120,6 +129,12 @@ function applyDirectWindowAnimation(windowId: AnyNodeId, value: number) {
   return false
 }
 
+function applyDirectWindowAnimation(windowId: AnyNodeId, value: number) {
+  const node = useScene.getState().nodes[windowId]
+  if (node?.type !== 'window') return false
+  return poseWindowMovingParts(node, sceneRegistry.nodes.get(windowId), value)
+}
+
 export const WindowAnimationSystem = () => {
   useFrame(({ clock }) => {
     const interactive = useInteractive.getState()