Update workflow: build for both Windows and Linux

.github/workflows/build.yml

@@ -7,7 +7,10 @@ on:
 
 jobs:
   build:
-    runs-on: windows-latest
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
     permissions:
       contents: write
     steps:
@@ -18,25 +21,47 @@ jobs:
         with:
           go-version: '1.22'
 
-      - name: Build
-        run: go build -ldflags "-s -w" -o mhr-cfw-go.exe ./cmd/mhr-cfw
+      - name: Build Linux
+        if: matrix.os == 'ubuntu-latest'
+        run: GOOS=linux go build -ldflags "-s -w" -o mhr-cfw-go ./cmd/mhr-cfw
+
+      - name: Build Windows
+        if: matrix.os == 'windows-latest'
+        run: GOOS=windows go build -ldflags "-s -w" -o mhr-cfw-go.exe ./cmd/mhr-cfw
 
       - name: Upload artifact
         uses: actions/upload-artifact@v4
         with:
-          name: mhr-cfw-go
-          path: mhr-cfw-go.exe
+          name: mhr-cfw-go-${{ matrix.os }}
+          path: mhr-cfw-go*
 
-      - name: Download artifact
+  release:
+    needs: build
+    runs-on: ubuntu-latest
+    if: startsWith(github.ref, 'refs/tags/')
+    permissions:
+      contents: write
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Download Linux artifact
         uses: actions/download-artifact@v4
         with:
-          name: mhr-cfw-go
+          name: mhr-cfw-go-ubuntu-latest
+          path: .
+
+      - name: Download Windows artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: mhr-cfw-go-windows-latest
           path: .
 
       - name: Release
         uses: softprops/action-gh-release@v2
         with:
-          files: mhr-cfw-go.exe
+          files: |
+            mhr-cfw-go
+            mhr-cfw-go.exe
           body: "Built from commit ${{ github.sha }}"
         env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}