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.date.to-primitive.js

@@ -0,0 +1,14 @@
+'use strict';
+var hasOwn = require('../internals/has-own-property');
+var defineBuiltIn = require('../internals/define-built-in');
+var dateToPrimitive = require('../internals/date-to-primitive');
+var wellKnownSymbol = require('../internals/well-known-symbol');
+
+var TO_PRIMITIVE = wellKnownSymbol('toPrimitive');
+var DatePrototype = Date.prototype;
+
+// `Date.prototype[@@toPrimitive]` method
+// https://tc39.es/ecma262/#sec-date.prototype-@@toprimitive
+if (!hasOwn(DatePrototype, TO_PRIMITIVE)) {
+  defineBuiltIn(DatePrototype, TO_PRIMITIVE, dateToPrimitive);
+}