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-ingress.yaml

@@ -0,0 +1,29 @@
+# vault.aleshym.co is PRIVATE. It is deliberately absent from the k3s
+# `catchall-to-docker-apps` public host list and from the Docker Traefik `wan`
+# entrypoint, so the internet has no route to it. Pi-hole resolves the name to
+# 10.10.0.100 for LAN/VPN clients.
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: vaultwarden
+  namespace: vaultwarden
+  annotations:
+    cert-manager.io/cluster-issuer: letsencrypt-prod
+    traefik.ingress.kubernetes.io/router.entrypoints: websecure
+spec:
+  ingressClassName: traefik
+  rules:
+    - host: vault.aleshym.co
+      http:
+        paths:
+          - path: /
+            pathType: Prefix
+            backend:
+              service:
+                name: vaultwarden
+                port:
+                  name: http
+  tls:
+    - hosts:
+        - vault.aleshym.co
+      secretName: vaultwarden-tls