initialize method
Initializes the SDK.
apiKey is optional. If not provided, the plugin searches for ZarliAPIKey
in the Info.plist (iOS) or AndroidManifest.xml (Android).
Implementation
@override
Future<void> initialize({String? apiKey}) async {
final Map<String, dynamic> args = {};
if (apiKey != null) {
args['apiKey'] = apiKey;
}
await methodChannel.invokeMethod<void>('initialize', args);
}