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/internals/is-regexp.js

@@ -0,0 +1,13 @@
+'use strict';
+var isObject = require('../internals/is-object');
+var classof = require('../internals/classof-raw');
+var wellKnownSymbol = require('../internals/well-known-symbol');
+
+var MATCH = wellKnownSymbol('match');
+
+// `IsRegExp` abstract operation
+// https://tc39.es/ecma262/#sec-isregexp
+module.exports = function (it) {
+  var isRegExp;
+  return isObject(it) && ((isRegExp = it[MATCH]) !== undefined ? !!isRegExp : classof(it) === 'RegExp');
+};