Session goes idle with 0 captured messages (monitorOffset stuck at 0)

[OneStepAt4time]

Description

A session went idle with status: "idle", monitorOffset: 0, byteOffset: 0, and messages: []. The session existed and was idle, but the monitor endpoint returned NOT_FOUND when querying with offset=0, and the session GET showed 0 messages captured. This means no output from that session was captured at all — even though the Claude Code session was doing actual work (verified by grep showing code changes in files).

Session details:

• Session ID: a0c45c00-ad1a-463b-a468-e4d92ada72eb
• workDir: D:\sparky_projects\glamour_snake

Expected Behavior

The monitor endpoint should return captured messages from the session, and monitorOffset should advance as messages are captured.

Steps to Reproduce

1. Create a session with workDir
2. Send a task to the session
3. Wait for it to complete/go idle
4. Query the monitor endpoint or session GET

Actual Result

Session shows status: "idle" but monitorOffset: 0, byteOffset: 0, messages: [], and the monitor endpoint returns NOT_FOUND.

Environment

• OS: Windows 11
• Aegis version: 0.5.2-alpha
• tmux: healthy