Statusline shows stale team name after TeamDelete

Description

After calling TeamDelete to clean up a team, the statusline continues to display the old team name. Restarting the session or calling TeamDelete again doesn't clear it. The team context appears deleted (TeamDelete returns success, TaskList returns empty), but the statusline still renders the stale team name.

Steps to reproduce

1. Create a team with TeamCreate (e.g., team name: retro-refactor)
2. Call TeamDelete to remove it
3. Observe: statusline still shows the old team name (e.g., harness-evolution-phase1-2)
4. Restart the session — statusline still shows the stale name
5. Call TeamDelete again — returns "No team name found, nothing to clean up" but statusline persists

Expected behavior

After TeamDelete succeeds, the statusline should no longer display the team name.

Actual behavior

The team name persists in the statusline indefinitely, even across session restarts.

Environment

• Claude Code CLI
• macOS (Darwin 24.6.0)
• Custom statusline script configured in settings.json