Added serialization support for Utf8String

src/Discord.Net.Serialization/Json/Converters/Primitives.String.cs

@@ -1,4 +1,5 @@
 using System.Text.Json;
+using System.Text.Utf8;
 
 namespace Discord.Serialization.Json.Converters
 {
@@ -39,4 +40,24 @@ namespace Discord.Serialization.Json.Converters
                 writer.WriteValue(value);
         }
     }
+
+    internal class Utf8StringPropertyConverter : IJsonPropertyConverter<Utf8String>
+    {
+        public Utf8String Read(PropertyMap map, ref JsonReader reader, bool isTopLevel)
+        {
+            if (isTopLevel)
+                reader.Read();
+            if (reader.ValueType != JsonValueType.String)
+                throw new SerializationException("Bad input, expected String");
+            return new Utf8String(reader.Value);
+        }
+        public void Write(PropertyMap map, ref JsonWriter writer, Utf8String value, bool isTopLevel)
+        {
+            //TODO: Serialization causes allocs, fix
+            if (isTopLevel)
+                writer.WriteAttribute(map.Utf16Key, value.ToString());
+            else
+                writer.WriteValue(value.ToString());
+        }
+    }
 }

src/Discord.Net.Serialization/Json/JsonFormat.cs

@@ -5,6 +5,7 @@ using System.Reflection;
 using System.Text;
 using System.Text.Formatting;
 using System.Text.Json;
+using System.Text.Utf8;
 
 namespace Discord.Serialization.Json
 {
@@ -28,6 +29,7 @@ namespace Discord.Serialization.Json
             
             //AddConverter<char, Converters.CharPropertyConverter>(); //char.Parse does not support Json.Net's serialization
             AddConverter<string, Converters.StringPropertyConverter>();
+            AddConverter<Utf8String, Converters.Utf8StringPropertyConverter>();
 
             AddConverter<DateTime, Converters.DateTimePropertyConverter>();
             AddConverter<DateTimeOffset, Converters.DateTimeOffsetPropertyConverter>();