Refactor Go CI workflow for better structure and coverage

Author: ismailtsdln

.github/workflows/go.yml

@@ -0,0 +1,65 @@
+name: Go CI / Test / Lint
+
+on:
+  push:
+    branches: [ "main" ]
+  pull_request:
+    branches: [ "main" ]
+
+jobs:
+  ci:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        go-version: [1.20, 1.21]
+
+    steps:
+    # Checkout code
+    - name: Checkout repository
+      uses: actions/checkout@v4
+
+    # Go setup
+    - name: Setup Go
+      uses: actions/setup-go@v4
+      with:
+        go-version: ${{ matrix.go-version }}
+
+    # Cache modules and build cache
+    - name: Cache Go build & modules
+      uses: actions/cache@v3
+      with:
+        path: |
+          ~/.cache/go-build
+          ~/go/pkg/mod
+        key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+        restore-keys: |
+          ${{ runner.os }}-go-
+
+    # Ensure dependencies
+    - name: Go mod tidy
+      run: go mod tidy
+
+    # Lint
+    - name: Run golangci-lint
+      uses: golangci/golangci-lint-action@v4
+      with:
+        version: v1.59.0
+        args: run --timeout 5m
+
+    # Build
+    - name: Build code
+      run: go build -v ./...
+
+    # Test + coverage
+    - name: Run tests with coverage
+      run: |
+        go test ./... -coverprofile=coverage.out -failfast -timeout=30s
+        go tool cover -func=coverage.out
+
+    # Upload coverage report (optional)
+    - name: Upload coverage to Codecov
+      if: github.event_name != 'pull_request'
+      uses: codecov/codecov-action@v4
+      with:
+        files: coverage.out