feat: build flutter use github action

.github/workflows/go.yml

@@ -29,6 +29,19 @@ jobs:
           registry: ${{ env.REGISTRY }}
           username: ${{ github.actor }}
           password: ${{ secrets.GHCR_TOKEN }}
+
+      - name: Set up Flutter
+        uses: subosito/flutter-action@v2
+        with:
+          channel: stable
+          flutter-version: 3
+
+      - name: Build Web
+        run: |
+          cd ui
+          flutter pub get
+          flutter build web --no-web-resources-cdn
+          
       - name: Extract metadata (tags, labels) for Docker
         id: meta
         uses: docker/metadata-action@v5