FRE-600: Fix code review blockers

- Consolidated duplicate UndoManagers to single instance
- Fixed connection promise to only resolve on 'connected' status
- Fixed WebSocketProvider import (WebsocketProvider)
- Added proper doc.destroy() cleanup
- Renamed isPresenceInitialized property to avoid conflict

Co-Authored-By: Paperclip <noreply@paperclip.ing>

src/lib/collaboration/yjs-document.ts

@@ -72,7 +72,7 @@ export function createScreenplayDoc(
   };
   
   // Initialize metadata if empty
-  if (meta.toJSON().length === 0) {
+  if (!meta.get('projectId')) {
     Object.entries(defaultMeta).forEach(([key, value]) => {
       meta.set(key as keyof ScreenplayMetadata, value);
     });