feat(auth): annuaire Authentik + portail consoles Guacamole (#76)

- k8s/apps/authentik : IdP OIDC (auth.lab.local), namespace auth —
  server + worker 2026.5.3, Redis in-cluster, PG sur storage-01, PVC media
- k8s/apps/guacamole : portail consoles SSH web s01/g01 (portail.lab.local) —
  guacd + webapp 1.6.0, SSO OIDC vers Authentik, Job initdb idempotent
- ansible : rôle console_user (user sans sudo pour les consoles, s01 + g01),
  bases PG authentik/guacamole, secrets vault (mdp PG + clé SSH console)
- doc : admin/k8s/auth-portal.md (déploiement, config initiale, pièges)

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

k8s/apps/guacamole/ingress.yaml

@@ -0,0 +1,14 @@
+apiVersion: traefik.io/v1alpha1
+kind: IngressRoute
+metadata:
+  name: guacamole
+  namespace: auth
+spec:
+  entryPoints:
+    - web
+  routes:
+    - match: Host(`portail.lab.local`)
+      kind: Rule
+      services:
+        - name: guacamole
+          port: 8080