loadEvent method
Loads the raw stored event by id.
Prefer loadEvents in app-facing read paths because loadEvent does not
itself promise visibility filtering.
Implementation
@override
Future<Nip01Event?> loadEvent(String id) async {
final data = await _eventsStore.record(id).get(_database);
if (data == null) return null;
return Nip01EventExtension.fromJsonStorage(data);
}