add converter and reader to interactionservice

src/Discord.Net.Interactions/InteractionService.cs

@@ -223,7 +223,8 @@ namespace Discord.Interactions
                 new ConcurrentDictionary<Type, Type>
                 {
                     [typeof(Array)] = typeof(DefaultArrayComponentConverter<>),
-                    [typeof(IConvertible)] = typeof(DefaultValueComponentConverter<>)
+                    [typeof(IConvertible)] = typeof(DefaultValueComponentConverter<>),
+                    [typeof(Nullable<>)] = typeof(NullableComponentConverter<>)
                 });
 
             _typeReaderMap = new TypeMap<TypeReader, string>(this, new ConcurrentDictionary<Type, TypeReader>(),
@@ -234,7 +235,8 @@ namespace Discord.Interactions
                     [typeof(IUser)] = typeof(DefaultUserReader<>),
                     [typeof(IMessage)] = typeof(DefaultMessageReader<>),
                     [typeof(IConvertible)] = typeof(DefaultValueReader<>),
-                    [typeof(Enum)] = typeof(EnumReader<>)
+                    [typeof(Enum)] = typeof(EnumReader<>),
+                    [typeof(Nullable<>)] = typeof(NullableReader<>)
                 });
         }
 

src/Discord.Net.Interactions/TypeConverters/ComponentInteractions/NullableComponentConverter.cs

@@ -18,6 +18,6 @@ namespace Discord.Interactions
         }
 
         public override Task<TypeConverterResult> ReadAsync(IInteractionContext context, IComponentInteractionData option, IServiceProvider services)
-            => _typeConverter.ReadAsync(context, option, services);
+            => string.IsNullOrEmpty(option.Value) ? Task.FromResult(TypeConverterResult.FromSuccess(null)) : _typeConverter.ReadAsync(context, option, services);
     }
 }

src/Discord.Net.Interactions/TypeReaders/NullableReader.cs

@@ -18,6 +18,6 @@ namespace Discord.Interactions
         }
 
         public override Task<TypeConverterResult> ReadAsync(IInteractionContext context, string option, IServiceProvider services)
-            => _typeReader.ReadAsync(context, option, services);
+            => string.IsNullOrEmpty(option) ? Task.FromResult(TypeConverterResult.FromSuccess(null)) : _typeReader.ReadAsync(context, option, services);
     }
 }