- Add state persistence (persistState/restoreState) for recovery after restart
- Add handleScheduledGatewayRestart method that:
- Persists current scheduler state to disk
- Sends final heartbeat to backend before shutdown
- Stops the calendar scheduler (pauses scheduled tasks)
- Add isRestartPending flag to prevent new slot processing during restart
- Add isScheduledGatewayRestart helper to detect restart events
- Update scheduler to detect and handle ScheduledGatewayRestart events
- Add new tools: harborforge_restart_status, harborforge_calendar_pause/resume
- Export isRestartPending and getStateFilePath methods
- Bump plugin version to 0.3.1