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/escalade/index.d.ts

@@ -0,0 +1,15 @@
+type Promisable<T> = T | Promise<T>;
+
+declare namespace escalade {
+	export type Callback = (
+		directory: string,
+		files: string[],
+	) => Promisable<string | false | void>;
+}
+
+declare function escalade(
+	directory: string,
+	callback: escalade.Callback,
+): Promise<string | void>;
+
+export = escalade;