fix produc domain name for the image creation

.gitlab-ci.yml

@@ -139,6 +139,22 @@ build_image:
     - echo "$REGISTRY_PASSWORD" | docker login "$REGISTRY_HOST" -u "$REGISTRY_USER" --password-stdin
   script:
     - echo "--- Building Docker Image ---"
+    - |
+      for var_name in NEXT_PUBLIC_API_URL NEXT_PUBLIC_MARKETPLACE_URL NEXT_PUBLIC_DASHBOARD_URL NEXT_PUBLIC_ADMIN_URL; do
+        var_value="$(printenv "$var_name" || true)"
+
+        if [ -z "$var_value" ]; then
+          echo "$var_name is not set. Refusing to build a production image with missing public frontend URLs." >&2
+          exit 1
+        fi
+
+        case "$var_value" in
+          *example.com*)
+            echo "$var_name=$var_value still uses the placeholder example.com domain. Update the GitLab CI/CD variable before building." >&2
+            exit 1
+            ;;
+        esac
+      done
     # NEXT_PUBLIC_* vars are inlined into Next.js bundles at build time — must be passed as ARGs
     - |
       docker build \