cleanup: remove quizmaster and leafweb (unused/orphaned), add watchtower monitor-only labels, minor consistency fixes

- quizmaster: removed entirely (test service, no longer used); also removed Portainer stack and /srv/quizmaster data
- leafweb: removed orphaned MSSQL compose file (no running container, no Portainer stack, no data on disk)
- authelia, gitea, couchdb, portainer, immich (server + ml): add com.centurylinklabs.watchtower.monitor-only=true so watchtower still notifies on new versions without auto-applying them
- ladder: restore restart: unless-stopped (was commented out)
- rackpeek: add missing TZ env var

portainer/docker-compose.yaml

@@ -4,6 +4,8 @@ services:
       container_name: portainer
       restart: always
       privileged: true
+      labels:
+        - com.centurylinklabs.watchtower.monitor-only=true
       volumes:
         - /mnt/containers/portainer/container-data/data:/data:Z
         - /var/run/docker.sock:/var/run/docker.sock:Z