feat(hub): v0.70.0 — a deleted customer actually disappears (residue leg + ghost cleanup)

Found validating v0.69.0 against the live hub. demo-vm-felhom was deleted
on 07-18 and was still on the Customers list AND still raising offsite_stale
(10 events, latest 07-21 17:34, operator email at 19:34) — because
GetCustomers() is report-derived and no lifecycle tier ever deleted a report.

New leg 3 (residue), before the record purge: reports, app_telemetry,
app_log_tails, log_tail_requests, customer_notifications, plus the
credential-bearing appliance_registrations and selfbind_tokens. Audit
(events, notification_log) and F-14 provenance still survive.

Ghost customers are now deletable: 404 means "nothing here", not "no config
row". With no config row the offsite descriptor is unknowable, so the Hetzner
and descriptor legs record skipped_no_config rather than a bare "skipped".

Two more red-proofs.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01J55BQE1gE2V4ffud5jweGS

manifests/hub.yaml

@@ -125,7 +125,7 @@ spec:
     spec:
       containers:
         - name: hub
-          image: gitea.dooplex.hu/admin/felhom-hub:0.69.0
+          image: gitea.dooplex.hu/admin/felhom-hub:0.70.0
           ports:
             - containerPort: 8080
               name: http