Add GitHub Actions workflow to auto-upload release assets

Co-authored-by: Project516 <138796702+Project516@users.noreply.github.com>

Author: Copilot

.github/workflows/release.yml

@@ -0,0 +1,41 @@
+name: Build and Upload Release Assets
+
+on:
+  release:
+    types: [created]
+
+jobs:
+  build-and-upload:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v5
+
+      - name: Set up JDK 25
+        uses: actions/setup-java@v5
+        with:
+          java-version: '25'
+          distribution: 'temurin'
+
+      - name: Setup Gradle
+        uses: gradle/actions/setup-gradle@v5
+
+      - name: Build JAR with Gradle
+        run: ./gradlew build
+
+      - name: Build Debian package
+        run: ./package-deb.sh
+
+      - name: Build ZIP archive
+        run: ./package.sh
+
+      - name: Upload release assets
+        uses: softprops/action-gh-release@v2
+        with:
+          files: |
+            ./app/build/libs/app.jar
+            ./numberguessinggame.deb
+            ./archive.zip