feat: Add multi-stage Docker build and GHCR publishing workflow

.github/workflows/ci.yml

@@ -62,3 +62,57 @@ jobs:
           else
             npm publish --access public
           fi
+
+  publish-docker:
+    runs-on: ubuntu-latest
+    # Triggers on official releases or manual alpha builds, matching NPM publish logic
+    if: github.event_name == 'release' || (github.event_name == 'workflow_dispatch' && github.event.inputs.publish_alpha == 'true')
+    needs: [test]
+    permissions:
+      contents: read
+      packages: write
+      attestations: write
+      id-token: write
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@v4
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Extract metadata (tags, labels) for Docker
+        id: meta
+        uses: docker/metadata-action@v6
+        with:
+          images: ghcr.io/${{ github.repository }}
+          tags: |
+            type=semver,pattern={{version}}
+            type=raw,value=alpha,enable=${{ github.event.inputs.publish_alpha == 'true' }}
+            type=edge,branch=main
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v4
+
+      - name: Build and push Docker image
+        id: push
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          file: dockerfile
+          push: true
+          platforms: linux/amd64,linux/arm64
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+
+      - name: Generate artifact attestation
+        uses: actions/attest-build-provenance@v4
+        with:
+          subject-name: ghcr.io/${{ github.repository }}
+          subject-digest: ${{ steps.push.outputs.digest }}
+          push-to-registry: true

dockerfile

@@ -0,0 +1,32 @@
+# Stage 1: Build
+FROM mirror.gcr.io/node:24-alpine AS builder
+
+WORKDIR /app
+
+# Copy package files from the local typescript example folder
+# Note: Path is relative to the root of the conformance repo
+COPY examples/servers/typescript/package*.json ./
+
+# Install all dependencies (including devDependencies needed for tsx)
+RUN npm ci
+
+# Copy the rest of the server source code
+COPY examples/servers/typescript/ ./
+
+# Stage 2: Production Release
+FROM mirror.gcr.io/node:24-alpine AS release
+
+WORKDIR /app
+
+# Copy only necessary built files and node_modules from builder stage
+COPY --from=builder /app/ ./
+
+# Set production environment variables
+ENV NODE_ENV=production
+ENV PORT=3000
+
+# Document the port usage
+EXPOSE 3000
+
+# Execution command
+CMD ["npm", "start"]