基于生产-消费模式，使用Channel进行文件传输（Tcp方式）

Client端：

#region 多文件传输
public class FileMetadata
{public string FileName { get; set; }public long FileSize { get; set; }
}class Program
{const int PORT = 8888;const int BUFFER_SIZE = 60 * 1024 * 1024;//15s-50  25s-64 33s-32 27s-50 31s-40 25s-60const int MAX_CHANNEL_CAPACITY = 1000;static async Task Main(){Console.WriteLine($"Client ready to send file ...");Stopwatch stopwatch = new Stopwatch();stopwatch.Start();var folderPath = @"D:\cuda";//"D:\TestImage\imagesbaiyou";await SendFolderAsync(folderPath, "192.168.10.147");stopwatch.Stop();Console.WriteLine($"Client Transfer file need {TimeSpan.FromMilliseconds(stopwatch.ElapsedMilliseconds)} Milliseconds");Console.ReadKey();}static async Task SendFolderAsync(string folderPath, string server){using var client = new TcpClient();await client.ConnectAsync(server, PORT);using var stream = client.GetStream();int i = 1;foreach (var filePath in Directory.GetFiles(folderPath)){await SendFileAsync(filePath, stream);Console.WriteLine($"Send file {i++} ...");}}static async Task SendFileAsync(string filePath, NetworkStream st