Shares of other services and RepoISO integration

- include SMB drop-ins from /etc/samba/smb.conf.d into the generated smb.conf
- keep smbd/nfs-server running while other services (/etc/exports.d, drop-ins) share,
  instead of disabling them when nasmon has no shares of its own
- list those shares read-only on /shares
- settings: RepoISO URL; poll its /api/integration/status, dashboard card, menu link,
  alerts for portal down, stale worker, failed jobs, unmounted publications

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -11,6 +11,10 @@ share management from the UI.
 * Service: `systemctl status nasmon` / `journalctl -u nasmon -f`
 * JSON API: `/api/status`, `/api/history?hours=24`, `/api/disks/<serial>/history?days=30`
 
+Integrates with RepoISO on the same host: shares of other services
+(`/etc/samba/smb.conf.d`, `/etc/exports.d`) are included and kept running,
+and RepoISO health is shown on the dashboard and alerted on.
+
 No authentication — designed for a LAN-only NAS (the `/shares` page can
 create SMB/NFS users and exports, so keep it off the public internet).