arrstack: rebuild adult tier on the shared-Postgres pattern

Replace the legacy adult sonarr/radarr/nzbget with the kids-tier pattern
(active-active -unkin fork on shared arrstack-postgres + Valkey, S3
MediaCover/Backup, exportarr metrics). The old adult apps held no data, so
the wipe is sanctioned.

- add sonarr-adult/radarr-adult/nzbget-adult (copies of the *-kids dirs):
  own DBs sonarr-adult-main/radarr-adult-main, Vault paths
  .../default/{sonarr,radarr}-adult(+-db), S3 prefixes sonarr-adult/
  radarr-adult, UrlBase + probe + exportarr paths /3aa168/{sonarr,radarr},
  media subPaths tvshows/adult + movies/adult, nzbget config PVC on
  cephrbd-fast-delete
- postgres: add managed roles sonarr-adult/radarr-adult, Database CRDs
  {sonarr,radarr}-adult-main, VaultStaticSecrets {sonarr,radarr}-adult-db
- remove legacy sonarr/radarr/nzbget dirs (incl. their gateway/httproute),
  managed roles sonarr/radarr, databases {sonarr,radarr}-main, VSS
  {sonarr,radarr}-db, and all kustomization entries

apps/base/arrstack/kustomization.yaml

@@ -15,12 +15,12 @@ resources:
   - backups-bucket.yaml
   - postgres
   - valkey
-  - sonarr
-  - radarr
   - prowlarr
-  - nzbget
   - sonarr-kids
   - radarr-kids
   - nzbget-kids
+  - sonarr-adult
+  - radarr-adult
+  - nzbget-adult
   - arrproxy
   - mediamover