Implement WebSocket client hook

[superposition]

Description

Create React hook for WebSocket connection to server.

Tasks

• Create hooks/useWebSocket.ts
• Implement auto-reconnect with exponential backoff
• Parse binary frames using protocol from @marigraph/core
• Dispatch updates to Zustand store
• Track connection status (connecting, connected, disconnected)
• Add connection status indicator component
• Handle SURFACE_FULL and SURFACE_DELTA messages
• Add manual reconnect button

Acceptance Criteria

• Connects to server automatically
• Reconnects on disconnect
• UI shows connection status

Labels

web-app, frontend, real-time