refactor(paint-slots): share scene IBL as viewer SceneEnvironment

Replace the editor-only EditorEnvironment wrapper with a SceneEnvironment
component exported from @pascal-app/viewer, mounted as an opt-in <Viewer>
child (still not baked into the Viewer component). One source of truth the
editor and the community public viewer both inject; embed/thumbnail
surfaces simply don't mount it. Sunset preset at environmentIntensity 0.6.

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

packages/editor/src/components/editor-environment.tsx

@@ -1,20 +0,0 @@
-'use client'
-
-import { Environment } from '@react-three/drei'
-import { Suspense } from 'react'
-
-/**
- * Scene IBL for the editor — drei's prefiltered environment map. Injected as a
- * <Viewer> *child* (not baked into the Viewer component) so read-only / embed
- * viewers don't pull the HDRI. This is what gives PBR metals their reflections
- * and lifts the lighting on vertical surfaces (walls), which flat directional +
- * hemisphere lights can't do alone. Intensity is dialled below the preset
- * default so it complements the scene lights rather than washing them out.
- */
-export function EditorEnvironment() {
-  return (
-    <Suspense fallback={null}>
-      <Environment preset="sunset" environmentIntensity={0.6} />
-    </Suspense>
-  )
-}

packages/editor/src/components/editor/index.tsx

@@ -7,7 +7,13 @@ import {
   spatialGridManager,
   useScene,
 } from '@pascal-app/core'
-import { type HoverStyles, InteractiveSystem, useViewer, Viewer } from '@pascal-app/viewer'
+import {
+  type HoverStyles,
+  InteractiveSystem,
+  SceneEnvironment,
+  useViewer,
+  Viewer,
+} from '@pascal-app/viewer'
 import { memo, type ReactNode, useCallback, useEffect, useRef, useState } from 'react'
 import { ViewerOverlay } from '../../components/viewer-overlay'
 import { ViewerZoneSystem } from '../../components/viewer-zone-system'
@@ -21,7 +27,6 @@ import {
 } from '../../lib/scene'
 import { initSFXBus } from '../../lib/sfx-bus'
 import useEditor from '../../store/use-editor'
-import { EditorEnvironment } from '../editor-environment'
 import { CeilingSelectionAffordanceSystem } from '../systems/ceiling/ceiling-selection-affordance-system'
 import { CeilingSystem } from '../systems/ceiling/ceiling-system'
 import { RoofEditSystem } from '../systems/roof/roof-edit-system'
@@ -603,7 +608,7 @@ const ViewerSceneContent = memo(function ViewerSceneContent({
   const noEditing = isVersionPreviewMode || isFirstPersonMode || isStudioMode
   return (
     <>
-      <EditorEnvironment />
+      <SceneEnvironment />
       {!(isFirstPersonMode || isStudioMode) && <SelectionManager />}
       {!noEditing && <BoxSelectTool />}
       {!noEditing && <NodeArrowHandles />}