fix(platform): apply production hardening from audit plan

Close billing, tenancy, migration, build, and CI/CD gaps identified in the
audit: wallet/gateway guards, full-UUID namespaces, idempotent migrations with
base schema, stateful service stability, safer Dockerfiles/git builds, and
platform chart hardening (Redis auth, RollingUpdate, backups, Swagger off).

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/helm/cloudhost-platform/templates/backend-deployment.yaml

@@ -9,8 +9,14 @@ metadata:
     {{- include "cloudhost-platform.labels" . | nindent 4 }}
 spec:
   replicas: {{ .Values.backend.replicas }}
+  # Zero-downtime rollouts: DB migrations run in a pre-upgrade hook Job, so the
+  # new pod only starts against a ready schema. The uploads PVC is RWO but
+  # local-path volumes pin pods to the same node, so surge pods can attach.
   strategy:
-    type: Recreate
+    type: RollingUpdate
+    rollingUpdate:
+      maxSurge: 1
+      maxUnavailable: 0
   selector:
     matchLabels:
       app: {{ include "cloudhost-platform.backend.fullname" . }}
@@ -72,6 +78,11 @@ spec:
               value: {{ include "cloudhost-platform.redis.fullname" . }}
             - name: REDIS_PORT
               value: "6379"
+            - name: REDIS_PASSWORD
+              valueFrom:
+                secretKeyRef:
+                  name: {{ include "cloudhost-platform.secretName" . }}
+                  key: redis-password
             - name: JWT_SECRET
               valueFrom:
                 secretKeyRef: