feat: add interactive web terminal for bot containers (#232)

* feat(terminal): add interactive web terminal for bot containers

Add WebSocket-based terminal endpoint (/container/terminal/ws) that
provides a full PTY shell session inside the bot's MCP container.
Extend the gRPC proto with pty and resize fields, implement PTY exec
on the container side using creack/pty, and add an xterm.js-based
terminal component in the frontend bot detail page.

* chore: add /mcp in .gitignore

* feat(terminal): add multi-tab support, localStorage cache, and reactivity fixes

- Support unlimited terminal tabs with add/close/switch
- Cache terminal content to localStorage via SerializeAddon for session persistence
- Use shallowReactive for tab objects to ensure status updates trigger UI reactivity
- Fix listener leak by tracking and disposing onData/onResize on reconnect
- Fix bottom clipping by using inset offsets instead of padding

.gitignore

@@ -93,6 +93,7 @@ tmp/
 # compiled files
 /memoh
 /agent
+/mcp
 
 docs/docs/.vitepress/cache
 .pnpm-store