Phase 2: deploy Authentik warm standby on the VPS

CNPG operator on the VPS (argocd-apps/vps-standby/cnpg-operator.yaml),
plus a CNPG 'replica cluster' for pg-authentik (infrastructure/
vps-standby/authentik/manifests/cnpg-cluster.yaml) that continuously
replays WAL shipped from home's pg-authentik via VPS MinIO's
cnpg-backups/pg-authentik bucket path - CNPG's native replica-cluster
mode, not a custom restore script like Vault needed (Vault has no
equivalent built-in continuous-replication-into-object-store feature).

The Authentik app itself runs at replicas: 0 in normal operation - the
replica DB is read-only until a deliberate manual promotion
(spec.replica.enabled: false), and a pod trying to write against a
read-only DB would just crashloop uselessly. values.yaml's authentik:
block is copied byte-identical from home's on purpose: the chart
deterministically derives its generated Secret's AUTHENTIK_SECRET_KEY
from these literal values.yaml strings, so both clusters land on the
same key without manually copying it - required since that key decrypts
things stored encrypted in the replicated DB.

infrastructure/vps-standby/authentik/manifests/presync-job.yaml

@@ -0,0 +1,87 @@
+---
+# Same idempotent secret-bootstrap pattern as home's
+# infrastructure/authentik/manifests/presync-job.yaml, scoped to a
+# dedicated ServiceAccount here (no shared argocd-hook-sa exists on the
+# vps-standby cluster the way it does at home).
+apiVersion: v1
+kind: ServiceAccount
+metadata:
+  name: authentik-hook
+  namespace: authentik
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: Role
+metadata:
+  name: authentik-hook
+  namespace: authentik
+rules:
+  - apiGroups: [""]
+    resources: ["secrets"]
+    verbs: ["get", "create"]
+  - apiGroups: ["postgresql.cnpg.io"]
+    resources: ["clusters"]
+    verbs: ["get"]
+---
+apiVersion: rbac.authorization.k8s.io/v1
+kind: RoleBinding
+metadata:
+  name: authentik-hook
+  namespace: authentik
+subjects:
+  - kind: ServiceAccount
+    name: authentik-hook
+    namespace: authentik
+roleRef:
+  kind: Role
+  name: authentik-hook
+  apiGroup: rbac.authorization.k8s.io
+---
+apiVersion: batch/v1
+kind: Job
+metadata:
+  name: authentik-presync
+  namespace: authentik
+  annotations:
+    argocd.argoproj.io/hook: PreSync
+    argocd.argoproj.io/hook-delete-policy: BeforeHookCreation
+spec:
+  backoffLimit: 3
+  template:
+    spec:
+      serviceAccountName: authentik-hook
+      restartPolicy: Never
+      securityContext:
+        runAsNonRoot: true
+        runAsUser: 65534
+        seccompProfile:
+          type: RuntimeDefault
+      containers:
+        - name: presync
+          image: alpine/k8s:1.32.13
+          securityContext:
+            allowPrivilegeEscalation: false
+            capabilities:
+              drop: ["ALL"]
+          command:
+            - /bin/bash
+            - -c
+            - |
+              set -euo pipefail
+              echo "=== Authentik (VPS) PreSync ==="
+
+              # NOTE: does NOT wait for pg-authentik to be "Healthy" the way
+              # home's presync-job does - a replica cluster in continuous
+              # recovery never reports Healthy in that sense (it's
+              # perpetually catching up / read-only), and server/worker are
+              # at replicas: 0 anyway so nothing actually needs the DB yet.
+
+              if ! kubectl -n authentik get secret authentik >/dev/null 2>&1; then
+                echo "Creating authentik secret (literal env:// placeholder -"
+                echo "matches home's values.yaml exactly, see values.yaml comment)..."
+                kubectl -n authentik create secret generic authentik \
+                  --from-literal=AUTHENTIK_SECRET_KEY="env://AUTHENTIK_SECRET_KEY"
+              else
+                echo "authentik secret already exists"
+              fi
+
+              echo "=== Done ==="