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/agentkeepalive/index.js

@@ -0,0 +1,7 @@
+'use strict';
+
+const HttpAgent = require('./lib/agent');
+module.exports = HttpAgent;
+module.exports.HttpAgent = HttpAgent;
+module.exports.HttpsAgent = require('./lib/https_agent');
+module.exports.constants = require('./lib/constants');