[BUG] Session list navigation (left arrow) permanently stops statusline refreshInterval for the session

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When I navigate to the session list (left arrow) and return to a session, the session's statusLine.command stops being called entirely. The statusline freezes at the last-rendered output indefinitely — even during active model responses.

What Should Happen?

refreshInterval should continue firing every 60s after returning to a session, as it did before navigation.

Error Messages/Logs

Steps to Reproduce

1. Configure statusLine: { type: "command", refreshInterval: 60 } in settings.json
2. Add a log line at the very top of the statusLine command script (e.g. printf '%s entry\n' "$(date +%s)" >> /tmp/statusline.log)
3. Open any session and confirm log entries appear every ~60s
4. Press left arrow to open the session list
5. Return to the same session (right arrow or select it)
6. Observe: one final log entry fires on focus-return, then nothing — even while the session is actively responding to messages

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.233 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Affected scope: any session that was active when the session list was opened. Sessions never navigated away from are unaffected. Multiple sessions freeze simultaneously if you navigate between several.

Related: #86785 reports the same refresh stoppage triggered by /compact — likely the same underlying timer-restart bug, different trigger.