deleteModel method
Deletes a model and all its files
Implementation
@override
Future<void> deleteModel(ModelSpec spec) async {
await _ensureInitialized();
// Clear all data for this model
_modelPaths.remove(spec.name);
_loraPaths.remove(spec.name);
_loadCompleters.remove(spec.name);
_installedModels.remove(spec.name);
debugPrint('WebModelManager: Model ${spec.name} deleted');
}