add ci workflow

Author: dank

.github/workflows/ci.yml

@@ -0,0 +1,23 @@
+name: CI
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-go@v5
+        with:
+          go-version-file: go.mod
+      - name: Format
+        run: test -z "$(gofmt -l .)"
+      - name: Vet
+        run: go vet ./...
+      - name: Build
+        run: go build ./...
+      - name: Test
+        run: go test -race ./...