feat(statehub): add railiance deployment manifests

deploy/railiance/platform/state-hub-db-cluster.yaml

@@ -0,0 +1,28 @@
+---
+# Dedicated CNPG Cluster for State Hub episodic memory.
+# Owned by railiance-platform (S3). Operator lives in cnpg-system.
+#
+# Pre-condition: state-hub-db-credentials Secret exists in databases namespace.
+# Runtime app Secret is separate and lives in the state-hub namespace.
+apiVersion: postgresql.cnpg.io/v1
+kind: Cluster
+metadata:
+  name: state-hub-db
+  namespace: databases
+  labels:
+    app.kubernetes.io/name: state-hub-db
+    app.kubernetes.io/component: database
+    app.kubernetes.io/managed-by: manual
+    railiance.io/layer: s3-platform
+    railiance.io/role: state-hub-database
+spec:
+  instances: 1
+  imageName: ghcr.io/cloudnative-pg/postgresql:16
+  storage:
+    size: 10Gi
+  bootstrap:
+    initdb:
+      database: state_hub
+      owner: state_hub
+      secret:
+        name: state-hub-db-credentials