Add GitHub Actions workflow to build and publish Android release APK

.github/workflows/android-release.yml

@@ -0,0 +1,84 @@
+name: Android Release APK
+
+'on':
+  push:
+    branches:
+      - main
+    tags:
+      - 'v*'
+  pull_request:
+    branches:
+      - main
+  workflow_dispatch:
+    inputs:
+      release_tag:
+        description: Optional tag to publish (example v1.0.0). Leave empty for build only.
+        required: false
+
+permissions:
+  contents: write
+
+jobs:
+  build_apk:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up JDK 17
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '17'
+
+      - name: Set up Gradle
+        uses: gradle/actions/setup-gradle@v4
+
+      - name: Build release APK
+        working-directory: android
+        run: ./gradlew --no-daemon assembleRelease
+
+      - name: Upload APK artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: app-release-apk
+          path: android/app/build/outputs/apk/release/app-release.apk
+
+  publish_release:
+    needs: build_apk
+    runs-on: ubuntu-latest
+    if: startsWith(github.ref, 'refs/tags/v') || (github.event_name == 'workflow_dispatch' && github.event.inputs.release_tag != '')
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Resolve release tag
+        run: |
+          if [ "${{ github.event_name }}" = "workflow_dispatch" ]; then
+            echo "RELEASE_TAG=${{ github.event.inputs.release_tag }}" >> "$GITHUB_ENV"
+          else
+            echo "RELEASE_TAG=${GITHUB_REF_NAME}" >> "$GITHUB_ENV"
+          fi
+
+      - name: Ensure tag exists for manual run
+        if: github.event_name == 'workflow_dispatch'
+        run: |
+          git config user.name "github-actions[bot]"
+          git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
+          git tag "$RELEASE_TAG" "${{ github.sha }}" || true
+          git push origin "$RELEASE_TAG"
+
+      - name: Download APK artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: app-release-apk
+          path: dist
+
+      - name: Attach APK to GitHub release
+        uses: softprops/action-gh-release@v2
+        with:
+          tag_name: ${{ env.RELEASE_TAG }}
+          generate_release_notes: true
+          files: dist/app-release.apk