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/eslint/lib/linter/index.js

@@ -0,0 +1,13 @@
+"use strict";
+
+const { Linter } = require("./linter");
+const interpolate = require("./interpolate");
+const SourceCodeFixer = require("./source-code-fixer");
+
+module.exports = {
+    Linter,
+
+    // For testers.
+    SourceCodeFixer,
+    interpolate
+};