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>

node_modules/core-js/modules/es.symbol.js

@@ -0,0 +1,7 @@
+'use strict';
+// TODO: Remove this module from `core-js@4` since it's split to modules listed below
+require('../modules/es.symbol.constructor');
+require('../modules/es.symbol.for');
+require('../modules/es.symbol.key-for');
+require('../modules/es.json.stringify');
+require('../modules/es.object.get-own-property-symbols');