Error toast after deleting sessions. - Failed to delete session: git ["fsmonitor--daemon", "stop"] failed: fatal: fsmonitor--daemon is not running

I haven't been able to figure out why this is happening but I often see the following error after deleting a session from the UI.

```
Delete failed
Failed to delete session: git ["fsmonitor--daemon", "stop"] failed: fatal: fsmonitor--daemon is not running
```

首先，在 GitHub Copilot 应用中复现会话删除，并跟踪调用 Git fsmonitor 的清理路径。确认当 fsmonitor--daemon 未运行时是否会发生错误，然后验证删除会话能够成功完成，且不会错误地显示失败提示 Toast。

由索引模型根据 Issue 内容生成。