Design and build the browser UI for a real-time collaborative whiteboard. People should be able to sketch on a canvas, add text, and drop basic shapes at the same time, seeing each other’s cursors and edits live. Include a compact tool palette and a properties panel with a subtle glassmorphism look. Each person must have their own undo/redo history that never rewinds other users’ actions. Users sign in with JWT and remain authenticated while working. Please implement this with React and TypeScript, manage state with Redux Toolkit, and connect to a WebSocket-based service (e.g., Pusher or your own server) for real-time updates.