Address PR review nitpicks:
- Add ClusterContextProvider to TestGracefulShutdownDuringIteration so
the scheduler loop actually starts (New() requires it).
- Wrap schedulerStatusPromise await in try/catch in plugin.templ so a
failed status fetch does not break refreshJobsAndActivities rendering.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>