P6: S3 blob store, Helm chart, air-gapped installer verify loop

- S3BlobStore (object_store, path-style) behind the same BlobStore trait,
  tested against a REAL MinIO container (round trip, overwrite, NotFound
  on get and delete, nested keys); [storage] backend=local|s3 config with
  validation + server-side selection (S3 creds via env overlay)
- Helm chart: server pod with the secret broker as a SIDECAR sharing a
  private emptyDir unix socket (no network hop carries credentials),
  frontend, optional local PVC vs S3, OIDC/oauth values, unbuffered-SSE
  ingress annotations, NetworkPolicies (frontend->server only), hardened
  securityContexts; ci/check-helm.sh lints AND asserts the rendered
  topology properties
- deploy/airgapped/install.sh: offline signature+checksum verification via
  the bundled teamclaw-bundler BEFORE any docker load; --verify-only mode;
  ci/test-install.sh rehearses clean/tampered/wrong-key paths with the
  real binary
- CI: helm gate + installer rehearsal wired in

149 Rust tests; helm lint + rendered assertions green; installer
verify-path rehearsal green.

Co-Authored-By: Claude Fable 5 <[email protected]>

deploy/helm/teamclaw/templates/ingress.yaml

@@ -0,0 +1,37 @@
+{{- if .Values.ingress.enabled }}
+# SSE streaming (POST /api/gateway) requires unbuffered proxying with long
+# read timeouts; without these annotations approvals and live transcripts
+# stall behind nginx buffering.
+apiVersion: networking.k8s.io/v1
+kind: Ingress
+metadata:
+  name: teamclaw
+  labels: {{- include "teamclaw.labels" . | nindent 4 }}
+  annotations:
+    nginx.ingress.kubernetes.io/proxy-buffering: "off"
+    nginx.ingress.kubernetes.io/proxy-read-timeout: "3600"
+    nginx.ingress.kubernetes.io/proxy-send-timeout: "3600"
+spec:
+  ingressClassName: {{ .Values.ingress.className }}
+  {{- if .Values.ingress.tlsSecretName }}
+  tls:
+    - hosts: [{{ .Values.ingress.host | quote }}]
+      secretName: {{ .Values.ingress.tlsSecretName }}
+  {{- end }}
+  rules:
+    - host: {{ .Values.ingress.host | quote }}
+      http:
+        paths:
+          - path: /api
+            pathType: Prefix
+            backend:
+              service:
+                name: teamclaw-server
+                port: { name: http }
+          - path: /
+            pathType: Prefix
+            backend:
+              service:
+                name: teamclaw-frontend
+                port: { name: http }
+{{- end }}