ci: add GitHub Actions workflow for test, build and docker verification

Run go vet, race tests and coverage upload on Go 1.24 and 1.25.

Build binaries for linux, windows and macos.

Verify Docker image build with Buildx and GHA cache.

Author: MasuRii

.github/workflows/ci.yml

@@ -0,0 +1,118 @@
+name: CI
+
+on:
+  push:
+    branches: [main, master]
+    paths-ignore:
+      - "**.md"
+      - "docs/**"
+      - "LICENSE"
+  pull_request:
+    branches: [main, master]
+    paths-ignore:
+      - "**.md"
+      - "docs/**"
+      - "LICENSE"
+
+permissions:
+  contents: read
+
+jobs:
+  # ---- Go test matrix ----
+  test:
+    name: Test (Go ${{ matrix.go-version }})
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        go-version: ["1.24", "1.25"]
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: ${{ matrix.go-version }}
+          cache: true
+
+      - name: Vet
+        run: go vet ./...
+
+      - name: Test
+        run: go test -race -coverprofile=coverage.out -covermode=atomic ./...
+
+      - name: Coverage report
+        uses: actions/upload-artifact@v4
+        if: always()
+        with:
+          name: coverage-go-${{ matrix.go-version }}
+          path: coverage.out
+
+  # ---- Binary build check ----
+  build:
+    name: Build (${{ matrix.os }})
+    runs-on: ${{ matrix.os }}
+    needs: test
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+        include:
+          - os: ubuntu-latest
+            binary: warpshift-linux-amd64
+          - os: windows-latest
+            binary: warpshift-windows-amd64.exe
+          - os: macos-latest
+            binary: warpshift-darwin-amd64
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: "1.24"
+          cache: true
+
+      - name: Build
+        run: |
+          go build -trimpath -ldflags="-s -w -X main.version=ci-${GITHUB_SHA::8}" -o "${{ matrix.binary }}" ./cmd/warpshift
+
+      - name: Verify binary
+        shell: bash
+        run: |
+          if [ ! -f "${{ matrix.binary }}" ]; then
+            echo "Binary not found: ${{ matrix.binary }}"
+            exit 1
+          fi
+          echo "Built: $(ls -lh ${{ matrix.binary }})"
+
+      - name: Upload binary
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{ matrix.binary }}
+          path: ${{ matrix.binary }}
+
+  # ---- Docker image build verification ----
+  docker-build:
+    name: Docker Build
+    runs-on: ubuntu-latest
+    needs: test
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Build Docker image
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          push: false
+          load: false
+          build-args: |
+            VERSION=ci-${GITHUB_SHA::8}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max