REFACTOR(repo): move vault/ to manifests/

- Move ExternalSecret files from vault/ to manifests/secret.yaml
- Merge multiple secrets with --- separator (postgresql)
- Update kustomization.yaml references
- Remove vault/ folders

Apps: postgresql, postgresql-dev, pgweb, minio, velero

postgresql/manifests/secret.yaml

@@ -0,0 +1,48 @@
+apiVersion: external-secrets.io/v1
+kind: ExternalSecret
+metadata:
+  name: postgresql-app-user
+  namespace: postgresql
+spec:
+  refreshInterval: 1h
+  secretStoreRef:
+    kind: ClusterSecretStore
+    name: vault-backend
+  target:
+    name: postgresql-app-user
+    creationPolicy: Owner
+    template:
+      type: kubernetes.io/basic-auth
+      data:
+        username: app
+        password: "{{ .password }}"
+  data:
+    - secretKey: password
+      remoteRef:
+        key: databases/postgresql
+        property: PASSWORD
+
+---
+apiVersion: external-secrets.io/v1
+kind: ExternalSecret
+metadata:
+  name: postgresql-superuser
+  namespace: postgresql
+spec:
+  refreshInterval: 1h
+  secretStoreRef:
+    kind: ClusterSecretStore
+    name: vault-backend
+  target:
+    name: postgresql-superuser
+    creationPolicy: Owner
+    template:
+      type: kubernetes.io/basic-auth
+      data:
+        username: postgres
+        password: "{{ .password }}"
+  data:
+    - secretKey: password
+      remoteRef:
+        key: databases/postgresql
+        property: PASSWORD