Remove the RepoISO integration; keep generic support for shares of other services

RepoISO now manages the NAS itself, so nasmon no longer polls it (settings field, dashboard card,
menu link and repoiso:* alerts are gone). Drop-in SMB includes, read-only listing and keeping
smbd/nfs-server running for other software's shares stay.

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

packaging/README.md

@@ -61,15 +61,3 @@ nasmon lists these shares read-only on /shares and keeps smbd / nfs-server
 enabled while any of them exist, even with no nasmon shares (previously it
 disabled the daemons and took such shares down). When SMB is switched off in
 nasmon, only nasmon's own shares are removed.
-
-## RepoISO integration
-
-Settings → Integrations → RepoISO URL (e.g. http://127.0.0.1). nasmon then
-polls <url>/api/integration/status every minute and
-
-* shows a RepoISO card on the dashboard (images, publications, jobs, Proxmox
-  exports, worker heartbeat) and a "RepoISO" menu link;
-* alerts: crit when the portal does not respond, warn when its worker has no
-  heartbeat, when jobs failed in the last 24 h or publications are not mounted.
-
-The status endpoint answers only on loopback, so use the local address.