private async IAsyncEnumerable<ListObjectsV2Response> EnumerateResponsesAsync(
    Func<ListObjectsV2Request> requestBuilder,
    [EnumeratorCancellation] CancellationToken cancellationToken)
{
    string? continuationToken = null;
    do
    {
        var request = requestBuilder();
        request.ContinuationToken = continuationToken;
        request.BucketName = _settings.S3.Bucket;

        var response = await s3.ListObjectsV2Async(request, cancellationToken);
        yield return response;

        continuationToken = response.IsTruncated == true ? response.NextContinuationToken : null;
    } while (continuationToken is not null);
}

private async IAsyncEnumerable<S3Object> EnumerateObjectsAsync(
    Func<ListObjectsV2Request> requestBuilder,
    [EnumeratorCancellation] CancellationToken cancellationToken)
{
    await foreach (var response in EnumerateResponsesAsync(requestBuilder, cancellationToken))
    {
        foreach (var obj in response.S3Objects ?? [])
            yield return obj;
    }
}