[Bug]: Background Codex memory activity appears in the active conversation #4683

Before submitting

• I searched existing issues and did not find a duplicate.
• I included enough detail to reproduce or investigate the problem.

Area

apps/server

Steps to reproduce

1. Open a normal T3 Code conversation using the Codex provider.
2. Exchange ordinary messages unrelated to any software project.
3. Allow the automatic post-turn memory consolidation to run.
4. Observe the active conversation after the background work starts.

In the observed case, commentary and file-read activity from separate background Codex turns appeared in the active conversation. The activity referenced memory-maintenance files and content from an unrelated workspace.

Expected behavior

Background memory-maintenance activity should remain isolated from the active conversation. Its messages, tool calls, filenames, and content from other workspaces should not be rendered in the user's chat.

Actual behavior

The background activity appeared in the current conversation, including references to unrelated project memory. Inspection showed that the ordinary Codex conversation transcript did not contain this activity, while T3's provider log recorded separate internal Codex threads under the same visible T3 conversation.

No full transcript, raw memory file, provider log, or screenshot is attached because each contains personal or project information. Sanitized diagnostics can be provided privately if needed.

Impact

Major degradation or frequent failure

This crosses conversation and workspace boundaries and can expose unrelated memory content in a personal chat.

Version or commit

0.0.29-nightly.20260724.893

Environment

Arch Linux, T3 Code desktop AppImage, Codex app-server provider, gpt-5.6-sol

Logs or stack traces

Sanitized event sequence:
- A normal assistant turn completed.
- A separate Codex provider thread started background memory consolidation.
- That background thread emitted commentary and file-read events.
- The events were associated with the active canonical T3 conversation and became visible there.

Workaround

No reliable workaround found. Avoiding or clearing the affected conversation does not address the underlying isolation problem.