Add TransferEncoding chunked

Author: mythz

src/ServiceStack.Text/HttpRequestConfig.cs

@@ -12,7 +12,9 @@ public class HttpRequestConfig
     public string? UserAgent { get; set; } 
     public string? ContentType { get; set; }
     public string? Referer { get; set; }
-    public string? Expect { get; set; } 
+    public string? Expect { get; set; }
+    public string[]? TransferEncoding { get; set; }
+    public bool? TransferEncodingChunked { get; set; }
     public NameValue? Authorization { get; set; }
     public LongRange? Range { get; set; }
     public List<NameValue> Headers { get; set; } = new();

src/ServiceStack.Text/HttpUtils.HttpClient.cs

@@ -1111,6 +1111,16 @@ public static HttpRequestMessage With(this HttpRequestMessage httpReq, Action<Ht
         if (config.Expect != null)
             httpReq.Headers.Expect.Add(new(config.Expect));
 
+        if (config.TransferEncodingChunked != null)
+            httpReq.Headers.TransferEncodingChunked = config.TransferEncodingChunked.Value;
+        else if (config.TransferEncoding?.Length > 0)
+        {
+            foreach (var enc in config.TransferEncoding)
+            {
+                httpReq.Headers.TransferEncoding.Add(new(enc));
+            }
+        }
+        
         foreach (var entry in headers)
         {
             httpReq.WithHeader(entry.Name, entry.Value);

src/ServiceStack.Text/HttpUtils.WebRequest.cs

@@ -1139,6 +1139,11 @@ public static HttpWebRequest With(this HttpWebRequest httpReq, Action<HttpReques
         if (config.Expect != null)
             httpReq.Expect = config.Expect;
 
+        if (config.TransferEncodingChunked != null)
+            httpReq.TransferEncoding = "chunked";
+        else if (config.TransferEncoding?.Length > 0)
+            httpReq.TransferEncoding = string.Join(", ", config.TransferEncoding);
+
         foreach (var entry in config.Headers)
         {
             httpReq.Headers[entry.Name] = entry.Value;