ci: add GitHub Actions workflow for release builds

- Build macOS app on tag push (v*)
- Create universal binary (arm64 + x86_64)
- Generate GitHub release with zipped app bundle
- Include installation instructions in release notes

Author: fxding

.github/workflows/release.yml

@@ -0,0 +1,74 @@
+name: Build and Release
+
+on:
+  push:
+    tags:
+      - 'v*'
+
+jobs:
+  build:
+    name: Build macOS App
+    runs-on: macos-latest
+    
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+      
+      - name: Select Xcode version
+        run: sudo xcode-select -s /Applications/Xcode.app/Contents/Developer
+      
+      - name: Show Xcode version
+        run: xcodebuild -version
+      
+      - name: Build app
+        run: |
+          xcodebuild -project forks.xcodeproj \
+            -scheme forks \
+            -configuration Release \
+            -derivedDataPath build \
+            -arch arm64 -arch x86_64 \
+            ONLY_ACTIVE_ARCH=NO \
+            CODE_SIGN_IDENTITY="-" \
+            CODE_SIGNING_REQUIRED=NO \
+            CODE_SIGNING_ALLOWED=NO \
+            build
+      
+      - name: Create app bundle
+        run: |
+          APP_PATH="build/Build/Products/Release/forks.app"
+          if [ -d "$APP_PATH" ]; then
+            cd build/Build/Products/Release
+            zip -r forks-macos.zip forks.app
+            mv forks-macos.zip ../../../../
+          else
+            echo "App bundle not found at $APP_PATH"
+            find build -name "*.app" -type d
+            exit 1
+          fi
+      
+      - name: Get tag name
+        id: tag
+        run: echo "TAG_NAME=${GITHUB_REF#refs/tags/}" >> $GITHUB_OUTPUT
+      
+      - name: Create Release
+        uses: softprops/action-gh-release@v1
+        with:
+          name: Forks ${{ steps.tag.outputs.TAG_NAME }}
+          draft: false
+          prerelease: false
+          files: |
+            forks-macos.zip
+          body: |
+            ## Forks ${{ steps.tag.outputs.TAG_NAME }}
+            
+            ### Installation
+            1. Download `forks-macos.zip`
+            2. Extract the zip file
+            3. Move `forks.app` to your Applications folder
+            4. Right-click and select "Open" (required for first launch since the app is not notarized)
+            
+            ### Requirements
+            - macOS 13.0 or later
+            - Node.js (for `npx skills` command)
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}