Add Android APK build to CI workflow

- New tauri-android-preview job for PR builds
- Installs Java 17, Android SDK, and Rust Android targets
- Builds debug APK using Tauri
- Uploads APK artifact for testing

Author: haslinghuis

.github/workflows/ci.yml

@@ -108,6 +108,67 @@ jobs:
           if-no-files-found: warn
           retention-days: 14
 
+  tauri-android-preview:
+    name: Tauri Android preview (APK)
+    runs-on: ubuntu-latest
+    needs: node-ci
+    if: ${{ github.event_name == 'pull_request' }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v5
+
+      - name: Setup Node
+        uses: actions/setup-node@v5
+        with:
+          node-version-file: '.nvmrc'
+          cache: 'yarn'
+
+      - name: Install dependencies
+        run: yarn install --frozen-lockfile
+
+      - name: Setup Java 17
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: '17'
+
+      - name: Setup Android SDK
+        uses: android-actions/setup-android@v3
+
+      - name: Install Rust
+        uses: dtolnay/rust-toolchain@stable
+
+      - name: Install Rust Android targets
+        run: |
+          rustup target add aarch64-linux-android
+          rustup target add armv7-linux-androideabi
+          rustup target add i686-linux-android
+          rustup target add x86_64-linux-android
+
+      - name: Build web assets (Vite)
+        run: yarn build
+
+      - name: Build Tauri Android APK
+        uses: tauri-apps/tauri-action@v0
+        with:
+          tauriScript: yarn tauri android build
+          includeUpdaterJson: false
+
+      - name: Inspect Android bundle output
+        if: always()
+        run: |
+          echo "Android APK artifacts:"
+          find src-tauri/gen/android -type f -name "*.apk" -print || true
+
+      - name: Upload Android APK
+        uses: actions/upload-artifact@v4
+        with:
+          name: android-apk
+          path: |
+            src-tauri/gen/android/app/build/outputs/apk/**/*.apk
+          if-no-files-found: warn
+          retention-days: 14
+
   docker-build:
     name: Docker build (optional)
     runs-on: ubuntu-latest