Improve message filtering in Neo API assistant stream processing

- Added filtering for 'function' type messages in requestMessages method
- Removed debug print statement in streamChat method
- Enhanced message handling to ignore function call messages during processing

This change refines the message filtering logic in the Neo API assistant, improving the clarity and efficiency of message stream processing.

neo/assistant/api.go

@@ -308,8 +308,6 @@ func (ast *Assistant) streamChat(
 				// 	msg.Write(c.Writer)
 				// }
 
-				fmt.Println("Done", contents.JSON())
-
 				res, hookErr := ast.HookDone(c, ctx, messages, contents)
 				if hookErr == nil && res != nil {
 
@@ -468,6 +466,12 @@ func (ast *Assistant) requestMessages(ctx context.Context, messages []chatMessag
 	length := len(messages)
 
 	for index, message := range messages {
+
+		// Ignore the function call message
+		if message.Type == "function" {
+			continue
+		}
+
 		role := message.Role
 		if role == "" {
 			return nil, fmt.Errorf("role must be string")