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/same-value.js

@@ -0,0 +1,8 @@
+'use strict';
+// `SameValue` abstract operation
+// https://tc39.es/ecma262/#sec-samevalue
+// eslint-disable-next-line es/no-object-is -- safe
+module.exports = Object.is || function is(x, y) {
+  // eslint-disable-next-line no-self-compare -- NaN check
+  return x === y ? x !== 0 || 1 / x === 1 / y : x !== x && y !== y;
+};