Add GitHub Actions workflow for builds and releases

Implements CI/CD pipeline that runs tests on every push/PR and creates multi-platform releases when tags are pushed.

Author: alex20465

.github/workflows/build-and-release.yml

@@ -0,0 +1,93 @@
+name: Build and Release
+
+on:
+  push:
+    branches:
+      - main
+    tags:
+      - 'v*'
+  pull_request:
+    branches:
+      - main
+
+permissions:
+  contents: write
+
+jobs:
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.23'
+
+      - name: Download dependencies
+        run: go mod download
+
+      - name: Run tests
+        run: go test -v ./...
+
+      - name: Build
+        run: go build -v ./cmd/clockwork
+
+  release:
+    name: Release
+    needs: test
+    if: startsWith(github.ref, 'refs/tags/v')
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        goos: [linux, darwin, windows]
+        goarch: [amd64, arm64]
+        exclude:
+          - goos: windows
+            goarch: arm64
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.23'
+
+      - name: Get version
+        id: version
+        run: echo "VERSION=${GITHUB_REF#refs/tags/}" >> $GITHUB_OUTPUT
+
+      - name: Build binary
+        env:
+          GOOS: ${{ matrix.goos }}
+          GOARCH: ${{ matrix.goarch }}
+        run: |
+          BINARY_NAME="clockwork-${{ steps.version.outputs.VERSION }}-${{ matrix.goos }}-${{ matrix.goarch }}"
+          if [ "${{ matrix.goos }}" = "windows" ]; then
+            BINARY_NAME="${BINARY_NAME}.exe"
+          fi
+          go build -ldflags="-s -w" -o "${BINARY_NAME}" ./cmd/clockwork
+
+      - name: Create checksum
+        run: |
+          BINARY_NAME="clockwork-${{ steps.version.outputs.VERSION }}-${{ matrix.goos }}-${{ matrix.goarch }}"
+          if [ "${{ matrix.goos }}" = "windows" ]; then
+            BINARY_NAME="${BINARY_NAME}.exe"
+          fi
+          sha256sum "${BINARY_NAME}" > "${BINARY_NAME}.sha256"
+
+      - name: Upload to release
+        uses: softprops/action-gh-release@v2
+        with:
+          files: |
+            clockwork-${{ steps.version.outputs.VERSION }}-${{ matrix.goos }}-${{ matrix.goarch }}*
+          draft: false
+          prerelease: false
+          generate_release_notes: true
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}