Move socket-related type definitions and schemas from cli and server packages
into a shared @hapi/protocol package for centralized type management. This
includes migrating Update types, socket event interfaces (ClientToServerEvents,
ServerToClientEvents), and terminal payload schemas. Add strongly-typed socket
handlers that reference the protocol package instead of duplicating definitions.
- Add CLI-side terminal management via Bun.Terminal with TerminalManager
- Implement server-side Socket.IO proxy for terminal I/O between web and CLI
- Create web terminal UI component with xterm.js and support for resize/reconnect
- Add terminal route and navigation button in session chat
- Include comprehensive terminal implementation plan and architecture docs