initialize method
Initializes the SDK. Idempotent; calling it again with the same config is a no-op.
Implementation
@override
Future<AdResult<void>> initialize(
NetworkConfig config, {
required bool testMode,
}) async {
initializeCalls++;
lastConfig = config;
lastTestMode = testMode;
if (initDelay > Duration.zero) await Future<void>.delayed(initDelay);
final error = initError;
if (error != null) return AdFailure(error.copyWith(network: network));
return const AdSuccess(null);
}