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-string.js

@@ -0,0 +1,20 @@
+'use strict';
+// TODO: Remove from `core-js@4`
+var uncurryThis = require('../internals/function-uncurry-this');
+var defineBuiltIn = require('../internals/define-built-in');
+
+var DatePrototype = Date.prototype;
+var INVALID_DATE = 'Invalid Date';
+var TO_STRING = 'toString';
+var nativeDateToString = uncurryThis(DatePrototype[TO_STRING]);
+var thisTimeValue = uncurryThis(DatePrototype.getTime);
+
+// `Date.prototype.toString` method
+// https://tc39.es/ecma262/#sec-date.prototype.tostring
+if (String(new Date(NaN)) !== INVALID_DATE) {
+  defineBuiltIn(DatePrototype, TO_STRING, function toString() {
+    var value = thisTimeValue(this);
+    // eslint-disable-next-line no-self-compare -- NaN check
+    return value === value ? nativeDateToString(this) : INVALID_DATE;
+  });
+}