chore(ci): Add keystore decode step to release workflow

Author: s4nj1th

.github/workflows/release.yml

@@ -32,6 +32,21 @@ jobs:
             - name: Get dependencies
               run: flutter pub get
 
+            - name: Decode keystore and write key.properties
+              env:
+                  KEYSTORE_BASE64: ${{ secrets.KEYSTORE_BASE64 }}
+                  KEYSTORE_PASSWORD: ${{ secrets.KEYSTORE_PASSWORD }}
+                  KEY_ALIAS: ${{ secrets.KEY_ALIAS }}
+                  KEY_PASSWORD: ${{ secrets.KEY_PASSWORD }}
+              run: |
+                  echo "$KEYSTORE_BASE64" | base64 -d > android/app/release-key.jks
+                  cat > android/key.properties <<EOF
+                  storeFile=release-key.jks
+                  storePassword=$KEYSTORE_PASSWORD
+                  keyAlias=$KEY_ALIAS
+                  keyPassword=$KEY_PASSWORD
+                  EOF
+
             - name: Build split APKs
               run: flutter build apk --release --split-per-abi