Configure app signing and add GitHub Actions release workflow

Author: harshitt13

.github/workflows/release.yml

@@ -0,0 +1,63 @@
+name: Flutter Android Release
+
+# Triggers the workflow when you push a tag like "v1.0.0"
+on:
+  push:
+    tags:
+      - 'v*' 
+
+jobs:
+  build:
+    name: Build & Release Signed App
+    runs-on: ubuntu-latest
+
+    permissions:
+      contents: write 
+
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+
+      - name: Set up Java
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: '17'
+
+      - name: Set up Flutter
+        uses: subosito/flutter-action@v2
+        with:
+          channel: 'stable'
+
+      - name: Install Dependencies
+        run: flutter pub get
+
+      # Decode the Base64 secret back into a physical file in the android/app folder
+      - name: Decode Keystore
+        run: echo "${{ secrets.KEYSTORE_BASE64 }}" | base64 --decode > android/app/upload-keystore.jks
+
+      # Build the signed App Bundle (.aab) while passing the passwords
+      - name: Build App Bundle
+        env:
+          KEYSTORE_PASSWORD: ${{ secrets.KEYSTORE_PASSWORD }}
+          KEY_PASSWORD: ${{ secrets.KEY_PASSWORD }}
+          KEY_ALIAS: ${{ secrets.KEY_ALIAS }}
+        run: flutter build appbundle --release
+
+      # Build the signed APK (.apk) just in case you want direct downloads too
+      - name: Build APK
+        env:
+          KEYSTORE_PASSWORD: ${{ secrets.KEYSTORE_PASSWORD }}
+          KEY_PASSWORD: ${{ secrets.KEY_PASSWORD }}
+          KEY_ALIAS: ${{ secrets.KEY_ALIAS }}
+        run: flutter build apk --release
+
+      # Create the GitHub Release and upload BOTH the .aab and .apk
+      - name: Create GitHub Release
+        uses: softprops/action-gh-release@v2
+        with:
+          files: |
+            build/app/outputs/bundle/release/app-release.aab
+            build/app/outputs/flutter-apk/app-release.apk
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}