Add vaultwarden app (migrated from docker on 10.10.0.5)

- Pinned to 1.37.0 so the migration is not also an upgrade
- ADMIN_TOKEN rotated to an Argon2id PHC string, stored as a SealedSecret.
  The old token was plaintext AND set in config.json, which overrides env --
  both that key and signups_allowed were removed during migration so the
  Deployment is the source of truth. signups had been silently enabled.
- /admin keeps Authentik forward-auth at priority 1000 (Traefik's default
  priority is rule length; the old docker router used 10 vs an implicit 24
  and was therefore bypassed).
- vault.aleshym.co stays private: absent from the k3s public catchall and
  from the Docker Traefik wan entrypoint.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

apps/vaultwarden/vaultwarden-pvc.yaml

@@ -0,0 +1,13 @@
+# local-path has reclaimPolicy: Delete -- deleting this PVC destroys the vault.
+# Data is tiny (12Mi today); 2Gi is headroom for attachments/sends.
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: vaultwarden-data
+  namespace: vaultwarden
+spec:
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 2Gi