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.reflect.prevent-extensions.js

@@ -0,0 +1,20 @@
+'use strict';
+var $ = require('../internals/export');
+var getBuiltIn = require('../internals/get-built-in');
+var anObject = require('../internals/an-object');
+var FREEZING = require('../internals/freezing');
+
+// `Reflect.preventExtensions` method
+// https://tc39.es/ecma262/#sec-reflect.preventextensions
+$({ target: 'Reflect', stat: true, sham: !FREEZING }, {
+  preventExtensions: function preventExtensions(target) {
+    anObject(target);
+    try {
+      var objectPreventExtensions = getBuiltIn('Object', 'preventExtensions');
+      if (objectPreventExtensions) objectPreventExtensions(target);
+      return true;
+    } catch (error) {
+      return false;
+    }
+  }
+});