public Task <Either <BaseError, string> > Handle(
     ScanLocalLibraryIfNeeded request,
     CancellationToken cancellationToken) => Handle(request);
 Task <Either <BaseError, string> > IRequestHandler <ScanLocalLibraryIfNeeded, Either <BaseError, string> > .Handle(
     ScanLocalLibraryIfNeeded request,
     CancellationToken cancellationToken) => Handle(request, cancellationToken);