listClientNames method
Returns the sorted names of every client directory, or an empty list
when the clients directory does not exist.
Implementation
Future<List<String>> listClientNames() async {
if (!clientsDir.existsSync()) return [];
final names = <String>[];
await for (final entity in clientsDir.list()) {
if (entity is Directory) names.add(p.basename(entity.path));
}
return names..sort();
}