Configure Firebase/Google Services support for Android and update the CI
build pipeline to use a newer NDK version.
- Add `google-services.json` and configure `googleServicesFile` in `app.json`
- Add `com.google.gms:google-services:4.4.4` classpath to build workflow
- Update Android NDK version from `27.0.12077973` to `27.1.12297006` in CI cache and installation steps
