feat(ci): build mobile debug APK

.github/workflows/mobile.yml

@@ -0,0 +1,57 @@
+name: Mobile
+
+on:
+  push:
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build_android:
+    name: Build Android APK
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout the repository
+        uses: actions/checkout@v6
+
+      - uses: pnpm/action-setup@v6
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v6
+        with:
+          node-version: 24
+          cache: "pnpm"
+
+      - name: Set up JDK 21
+        uses: actions/setup-java@v5
+        with:
+          distribution: temurin
+          java-version: 21
+
+      - name: Set up Gradle
+        uses: gradle/actions/setup-gradle@v5
+
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile
+
+      - name: Update build info
+        run: pnpm run chore:update-build-info
+
+      - name: Build client-standalone (webDir for Capacitor)
+        run: pnpm --filter @triliumnext/mobile build
+
+      - name: Sync Capacitor Android project
+        run: pnpm --filter @triliumnext/mobile exec cap sync android
+
+      - name: Assemble debug APK
+        working-directory: apps/mobile/android
+        run: ./gradlew assembleDebug --no-daemon
+
+      - name: Upload APK
+        uses: actions/upload-artifact@v7
+        with:
+          name: trilium-mobile-debug-apk
+          path: apps/mobile/android/app/build/outputs/apk/debug/*.apk
+          retention-days: 14