fix: Add skipEmptyWalArchiveCheck annotation and B2 secret healthcheck to CNPG

- Skip WAL archive emptiness check so recovery works when restoring over
  an existing backup archive in B2
- Add healthCheck for b2-credentials secret in CNPG kustomization to
  prevent recovery from starting before ExternalSecret has synced

infrastructure/addons/cnpg/postgres-cluster.yaml

@@ -3,6 +3,8 @@ kind: Cluster
 metadata:
   name: rancher-db
   namespace: cnpg-cluster
+  annotations:
+    cnpg.io/skipEmptyWalArchiveCheck: "enabled"
 spec:
   description: "Rancher external database cluster"
   imageName: ghcr.io/cloudnative-pg/postgresql:17.4

infrastructure/addons/kustomization-cnpg.yaml

@@ -14,4 +14,10 @@ spec:
   timeout: 10m
   suspend: false
   dependsOn:
-    - name: addon-cnpg-operator
+    - name: addon-cnpg-operator
+    - name: addon-external-secrets
+  healthChecks:
+    - apiVersion: v1
+      kind: Secret
+      name: b2-credentials
+      namespace: cnpg-cluster