Add GitHub Actions workflows for CI and release pipelines

- Implemented a CI workflow to run build, tests, and validation on push and pull request events.
- Added a release workflow to build binaries for multiple platforms/architectures and publish them as GitHub releases.

Author: rolling-space

.github/workflows/ci.yml

@@ -0,0 +1,47 @@
+name: CI
+
+on:
+  push:
+    branches: [ main, master, "**" ]
+  pull_request:
+    branches: [ main, master, "**" ]
+
+permissions:
+  contents: read
+
+jobs:
+  build-test:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.21'
+          check-latest: true
+
+      - name: Cache Go modules
+        uses: actions/cache@v4
+        with:
+          path: |
+            ~/.cache/go-build
+            ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+
+      - name: Ensure go.mod is tidy
+        run: |
+          go mod tidy
+          git diff --exit-code -- go.mod go.sum
+
+      - name: Build library layer
+        run: go build ./internal
+
+      - name: Build CLI
+        run: go build .
+
+      - name: Unit tests (internal only)
+        run: go test -v ./internal

.github/workflows/release.yml

@@ -0,0 +1,69 @@
+name: Release
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+permissions:
+  contents: write
+
+jobs:
+  build-and-release:
+    name: Build ${{ matrix.goos }}-${{ matrix.goarch }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        goos: [linux, darwin]
+        goarch: [amd64, arm64]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.21'
+          check-latest: true
+
+      - name: Cache Go modules
+        uses: actions/cache@v4
+        with:
+          path: |
+            ~/.cache/go-build
+            ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+
+      - name: Build binary
+        env:
+          CGO_ENABLED: 0
+          GOOS: ${{ matrix.goos }}
+          GOARCH: ${{ matrix.goarch }}
+        run: |
+          mkdir -p dist
+          BIN_NAME=pumadevctl
+          OUT=dist/${BIN_NAME}_${GOOS}_${GOARCH}
+          go build -trimpath -ldflags "-s -w" -o "$OUT" .
+          tar -C dist -czf "${OUT}.tar.gz" "${BIN_NAME}_${GOOS}_${GOARCH}"
+
+      - name: Create GitHub Release (if not exists)
+        id: create_release
+        uses: softprops/action-gh-release@v2
+        with:
+          draft: false
+          prerelease: false
+          name: ${{ github.ref_name }}
+          tag_name: ${{ github.ref_name }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Upload assets
+        uses: softprops/action-gh-release@v2
+        with:
+          files: |
+            dist/pumadevctl_${{ matrix.goos }}_${{ matrix.goarch }}.tar.gz
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}