ci: build with Gradle on GitHub Actions

.github/workflows/build-gradle-project.yml

@@ -0,0 +1,33 @@
+name: Build Gradle project
+
+on:
+  push:
+
+jobs:
+  build-gradle-project:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout project sources
+        uses: actions/checkout@v4
+
+      - name: Setup Java
+        uses: actions/setup-java@v4
+        with:
+          java-version: '17'
+          distribution: 'temurin'
+
+      - name: Setup Gradle
+        uses: gradle/actions/setup-gradle@v3
+        with:
+          build-scan-publish: true
+          build-scan-terms-of-use-url: "https://gradle.com/terms-of-service"
+          build-scan-terms-of-use-agree: "yes"
+
+      - name: Run build
+        run: ./gradlew build
+
+      - name: Upload build artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: Package
+          path: entrypoints/papermc/build/libs