ensureFlutterSdkDependency method
Ensures that package exists as a Flutter SDK dependency.
Adds the dependency with the Flutter SDK source if it is not already present.
Implementation
Future<void> ensureFlutterSdkDependency(String package) async {
final dependencies = _dependencies();
if (dependencies.containsKey(package)) return;
await _set(['dependencies', package], {'sdk': 'flutter'});
LoggerService.success('Added Flutter dependency: $package');
}