RAIL-HO-WP-0005-T09: Forgejo backup/restore drill assets and evidence

Add isolated-namespace restore drill (CNPG cluster, PVC, orchestration script)
and document successful 2026-07-04 run: production forgejo dump restored with
health 200 and pilot repos visible via API. Scheduled backups remain open.

infra/forgejo-restore-drill/forgejo-db-restore-cluster.yaml

@@ -0,0 +1,21 @@
+---
+apiVersion: postgresql.cnpg.io/v1
+kind: Cluster
+metadata:
+  name: forgejo-db-restore
+  namespace: forgejo-restore-drill
+  labels:
+    app.kubernetes.io/name: forgejo-db-restore
+    railiance.io/layer: s3-platform
+    railiance.io/consumer: forgejo-restore-drill
+spec:
+  instances: 1
+  imageName: ghcr.io/cloudnative-pg/postgresql:16
+  storage:
+    size: 10Gi
+  bootstrap:
+    initdb:
+      database: forgejo
+      owner: forgejo
+      secret:
+        name: forgejo-db-credentials

infra/forgejo-restore-drill/restore-job.yaml

@@ -0,0 +1,12 @@
+apiVersion: v1
+kind: PersistentVolumeClaim
+metadata:
+  name: forgejo-restore-data
+  namespace: forgejo-restore-drill
+spec:
+  accessModes:
+    - ReadWriteOnce
+  resources:
+    requests:
+      storage: 10Gi
+  storageClassName: local-path