fix: handle LM Studio disconnect gracefully during generation

[VforVitorio]

Problem

When LM Studio is closed (or the server stops) while lmcode is mid-generation, a raw traceback is printed to the terminal — likely an httpx connection error or an LM Studio SDK exception. The user sees a crash instead of a clean message.

Expected behaviour

Catch the disconnect and show something like:

LM Studio disconnected. Press Ctrl+C to exit or restart lmcode.

Or exit cleanly with a one-liner:

error: lost connection to LM Studio — exiting.

Implementation notes

• The error likely surfaces as an httpx.RemoteProtocolError, httpx.ConnectError, websockets.exceptions.ConnectionClosedError, or an lmstudio.LMStudioClientError raised inside model.act() in Agent._run_turn().
• Wrap await model.act(...) (and possibly the outer Agent.run() connection block) with a catch for those exception types.
• Print a clean Rich message using ERROR color and a Rule separator, then either loop back to prompt (with reconnect logic) or exit via sys.exit(1).
• If looping back, the chat history is still intact and the user can reconnect by restarting LM Studio and pressing Enter.

Related

• Similar graceful handling was added for Ctrl+C in feat: Ctrl+C interrupt mid-generation + suppress SDK noise #69.

[VforVitorio]

Fixed in v0.6.0 via PR #72. LM Studio disconnects now show a clean message instead of a traceback, and WebSocket JSON noise is suppressed via both stderr and logging.lastResort wrapping.