Handle execution errors by appending them to the result.

Previously, execution errors were only returned in the refusal field. This update appends errors to the result field if present, ensuring they are included in the tool's output. This change improves visibility and clarity for error reporting.

llm.go

@@ -2,6 +2,7 @@ package go_llm
 
 import (
 	"context"
+
 	"github.com/sashabaranov/go-openai"
 )
 
@@ -155,10 +156,17 @@ func (t ToolCallResponse) toChatCompletionMessages() []openai.ChatCompletionMess
 		refusal = t.Error.Error()
 	}
 
+	if refusal != "" {
+		if t.Result != "" {
+			t.Result = t.Result + " (error in execution: " + refusal + ")"
+		} else {
+			t.Result = "error in execution:" + refusal
+		}
+	}
+
 	return []openai.ChatCompletionMessage{{
 		Role:       openai.ChatMessageRoleTool,
 		Content:    t.Result,
-		Refusal:    refusal,
 		ToolCallID: t.ID,
 	}}
 }