ci: Install Node.js in workflow for actions support

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Co-Authored-By: Claude <noreply@anthropic.com>

.gitea/workflows/build-container.yml

@@ -15,6 +15,10 @@ jobs:
   build:
     runs-on: docker
     steps:
+      - name: Install Node.js
+        run: |
+          apk add --no-cache nodejs npm || apt-get update && apt-get install -y nodejs npm || yum install -y nodejs npm
+
       - name: Checkout
         uses: actions/checkout@v4