add lint check

.github/workflows/go.yml

@@ -15,6 +15,15 @@ jobs:
       uses: actions/setup-go@v5
       with:
         go-version: '1.22'
+    - name: Format check
+      run: |
+        if [ "$(gofmt -s -l . | wc -l)" -gt 0 ]; then
+          echo "Code is not formatted. Run 'go fmt ./...'"
+          gofmt -s -l .
+          exit 1
+        fi
+    - name: Vet
+      run: go vet ./...
     - name: Build
       run: go build -v ./...
     - name: Test