[Pi/ACP] Extension slash commands leave turns stuck indefinitely #1073

Summary

Pi extension slash commands can leave the Pi turn stuck in Codeg: the UI stays in a running/Prompting state, shows no command output or error, and does not accept the next turn until I cancel or restart the session.

This is not specific to pi-purge. I have seen the same symptom with multiple Pi extension projects that provide slash commands. pi-purge is one concrete example, not the subject of the report. The common pattern appears to be a command registered by an extension that completes without starting a model/agent loop.

Environment

• OS: Windows
• Codeg: 0.41.3
• Pi: 1.4.0
• pi-acp: 0.0.34 (reported by Codeg in its ACP connection log)
• Node.js: 24.14.1

Steps to reproduce

1. Install/load a Pi extension that provides a slash command. For a concrete example, I have pi-purge 0.2.4 installed.
2. Start Codeg and select the Pi agent.
3. Send an extension command such as /purge status.
4. Observe that the turn remains active and the UI does not show the command result.

I have observed the same general behavior with multiple extension projects, so pi-purge is only an example. The standalone Pi terminal UI handles the command normally.

Expected behavior

The extension command result/notification should be surfaced and the turn should complete. If extension commands are unsupported, Codeg should show a clear error and complete the request rather than leaving it pending indefinitely.

Actual behavior

• No visible command result or error is shown.
• The turn remains in a running/Prompting state indefinitely.
• Subsequent messages are blocked or queued behind the unresolved turn.
• I have to cancel the turn to recover.

The Codeg log shows the turn entering Prompting:

[ACP] status_changed ... Connected -> Prompting

After I cancel it, the log records stop_reason=cancelled; I do not see a normal completion for the extension command.

Related pi-acp issue

This appears related to svkozak/pi-acp#84, which reports that session/prompt never resolves for extension slash commands that do not start an agent loop. PR #118 proposes a fix for extension-only commands.

Codeg reports pi-acp 0.0.34 in its connection log. Could you confirm whether that bundled adapter includes the fix from #118? If not, could Codeg update its adapter? If it does, there may be an additional Codeg-side issue preventing the command result from being displayed or the turn from completing.