fix(cloud): restore disabled Box production mode

.github/workflows/deploy-prod.yml

@@ -57,22 +57,3 @@ jobs:
             ${{ env.CLOUD_IMAGE }}:deploy-prod
           cache-from: type=gha,scope=cloud-core-prod
           cache-to: type=gha,mode=max,scope=cloud-core-prod
-      - name: Configure SSH
-        env:
-          SSH_KEY: ${{ secrets.JP09_SSH_KEY }}
-          KNOWN_HOSTS: ${{ secrets.JP09_KNOWN_HOSTS }}
-        run: |
-          install -m 700 -d ~/.ssh
-          install -m 600 /dev/null ~/.ssh/id_ed25519
-          printf '%s\n' "$SSH_KEY" > ~/.ssh/id_ed25519
-          printf '%s\n' "$KNOWN_HOSTS" > ~/.ssh/known_hosts
-      - name: Upload release manifest and deploy
-        env:
-          HOST: ${{ secrets.JP09_HOST }}
-          USER: ${{ secrets.JP09_USER }}
-          PORT: ${{ secrets.JP09_PORT }}
-        run: |
-          remote="$USER@$HOST"
-          ssh -p "$PORT" "$remote" 'install -d -m 700 /opt/langbot-cloud-prod'
-          scp -P "$PORT" deploy/prod/docker-compose.yml deploy/prod/deploy.sh "$remote:/opt/langbot-cloud-prod/"
-          ssh -p "$PORT" "$remote" "chmod 700 /opt/langbot-cloud-prod/deploy.sh && /opt/langbot-cloud-prod/deploy.sh prod-${GITHUB_SHA}"

src/langbot/pkg/cloud/bootstrap.py

@@ -138,8 +138,14 @@ class VerifiedCloudDeployment:
         if plugin_worker.get('require_hard_limits') is not True:
             raise CloudBootstrapError('Cloud Runtime requires plugin.worker.require_hard_limits=true')
         box_config = config.get('box', {})
-        if box_config.get('enabled') is not True:
+        box_enabled = box_config.get('enabled')
-            raise CloudBootstrapError('Cloud runtime requires box.enabled=true')
+        if box_enabled is False:
+            # Explicitly disabling Box removes the sandbox surface entirely and
+            # therefore does not weaken tenant isolation. Validate the strict
+            # runtime/admission contract only when the surface is enabled.
+            return
+        if box_enabled is not True:
+            raise CloudBootstrapError('Cloud runtime requires box.enabled to be an explicit boolean')
         if box_config.get('backend') != 'nsjail':
             raise CloudBootstrapError('Cloud runtime requires box.backend=nsjail')
         runtime_endpoint = str(box_config.get('runtime', {}).get('endpoint', '') or '').strip()

tests/unit_tests/cloud/test_bootstrap.py

@@ -228,10 +228,23 @@ async def test_cloud_pgvector_contract_is_fail_closed(pgvector_config, message):
         )
 
 
+async def test_cloud_runtime_allows_explicitly_disabled_box():
+    config = _cloud_config()
+    config['box']['enabled'] = False
+
+    deployment = await resolve_deployment(
+        instance_uuid='instance-a',
+        instance_config=config,
+        entry_points=lambda: _EntryPoints([_EntryPoint(_Provider())]),
+        now=1_000,
+    )
+
+    assert isinstance(deployment, VerifiedCloudDeployment)
+
+
 @pytest.mark.parametrize(
     ('mutate', 'message'),
     [
-        (lambda config: config['box'].update(enabled=False), 'box.enabled=true'),
         (lambda config: config['box'].update(backend='docker'), 'box.backend=nsjail'),
         (lambda config: config['box']['runtime'].update(endpoint=''), 'box.runtime.endpoint'),
         (