infra: 2026-10-26 version audit, upgrades, UniFi re-removal

- Synapse v1.163.2, MAS 1.27.1, Traefik v3.7, node-exporter v1.12.1 (all
  nodes), cadvisor -> ghcr.io v0.60.6, alertmanager-receiver 2026.9.23,
  Gitea 1.26.4, Jellyfin 12.3, Seerr v3.5.1
- Watchtower -> nickfedor/watchtower fork, twice daily (04:00/16:00)
- Monitoring legacy node-exporter gated behind a compose profile
- unifi-os-server on .100 removed again; compose file renamed so it
  cannot be revived
- CLAUDE.md: Known Issues #40-43, service tree updates

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NQhgEUqcaV4WM2S4hfXgHD

compose/hf-pdocker-02/unifi/DECOMMISSIONED.txt

@@ -0,0 +1,3 @@
+Decommissioned 2026-10-05 and again 2026-10-26 (it had been revived and was running).
+Duplicate controller; the real UniFi controller is the Podman UniFi OS Server on .150.
+Do NOT compose up. Data kept in /var/lib/unifi-os (.100) + /mnt/docker-data/configs/unifi-os/persistent.