fix(office-ui): resolve blank/frozen office canvas and add sidebar collapse

Office canvas fixes:
- Lazy-create the Phaser game via ResizeObserver on the first non-zero
  layout instead of creating it inside the display:none office page with
  inline px fallback sizes. Phaser's RESIZE-mode 500ms parent poll has no
  zero guard, so the old path shrank the canvas to 0x0 (blue-black screen)
  and later restored it to a stale wrong size (clipped office).
- On unhide, re-measure with scale.getParentBounds() before scale.refresh();
  plain scale.resize() is clobbered by the stale cached parentSize in
  RESIZE mode.
- Fix whole-game freeze when clicking an office card: camera effects
  resolve ease names via EaseMap, which has no 'Cubic.Out' key, leaving
  effect.ease undefined and killing the RAF loop with a per-frame
  TypeError. Use 'Cubic.easeOut' for cam.pan in panToOffice/resetCameraView.
- Bound GameBridge queues (latest snapshot supersedes, event queue capped)
  since game creation is now deferred until the Office page is first opened.

Sidebar:
- Add a collapse/expand handle on the canvas/sidebar boundary with a 220ms
  grid transition; state persists in localStorage. The canvas follows the
  column change automatically through the ResizeObserver path. Stacked
  (<=1024px) layout collapses the bottom panel and moves the handle to the
  bottom edge.

README:
- Add Simplified Chinese translation (README.zh-CN.md) with a language
  switcher in both files; fix stale TOC entries in the English README.

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

opc/plugins/office_ui/frontend_src/game/GameBridge.ts

@@ -36,6 +36,7 @@ export class GameBridge extends Phaser.Events.EventEmitter {
   pushEvent(evt: VisualEvent) {
     if (!this.scene) {
       this.eventQueue.push(evt)
+      if (this.eventQueue.length > 500) this.eventQueue.shift()
       return
     }
     this.applyEvent(evt)
@@ -45,7 +46,11 @@ export class GameBridge extends Phaser.Events.EventEmitter {
     const agentCount = Object.keys(snapshot.agents ?? {}).length
     if (!this.scene) {
       console.log(`[GameBridge] pushSnapshot queued (scene not ready) — ${agentCount} agents`)
-      this.snapshotQueue.push(snapshot)
+      // A snapshot fully resets the scene, so it supersedes anything queued
+      // before it. The game may not be created until the Office page is first
+      // opened — keep the queues bounded in the meantime.
+      this.snapshotQueue = [snapshot]
+      this.eventQueue = []
       return
     }
     console.log(`[GameBridge] pushSnapshot applying now — ${agentCount} agents`)