Add GitHub Actions workflow to build Android APK

.github/workflows/android-build.yml

@@ -0,0 +1,43 @@
+name: Build Android APK
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+
+permissions:
+  contents: write
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Java 17
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: 17
+
+      - name: Set up Gradle
+        uses: gradle/actions/setup-gradle@v4
+
+      - name: Make Gradle wrapper executable
+        run: chmod +x gradlew
+
+      - name: Build debug APK
+        run: ./gradlew assembleDebug
+
+      - name: Upload APK to latest release
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: latest
+          name: Latest APK
+          files: app/build/outputs/apk/debug/app-debug.apk
+          make_latest: true
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}