Convert the three *arr apps from single-replica upstream LinuxServer/SQLite to
our -unkin2 forks running active-active (replicas 3) on a shared CNPG Postgres
cluster.
- new apps/base/arrstack/postgres/: CNPG Cluster arrstack-postgres (3 instances,
3 managed login roles sonarr/radarr/prowlarr, throwaway initdb owner), per-app
Database CRDs (<app>-main), cephrgw backup bucket + nightly ScheduledBackup,
and 3 VaultStaticSecrets syncing the <app>-db role credentials.
- per app: image -> docker-internal/<app>:v<base>-unkin2; replicas 3 +
RollingUpdate; drop the apikey-init initContainer + PUID/PGID/TZ; run the
binary directly with -nosingleinstancecheck; env from a new ConfigMap plus
Postgres user/password and the API key from Secrets; /config PVC -> RWX
cephfs-raid5-retain (shared).