fix: 修复配置指向的错误 (#168)

config/config.go

@@ -124,7 +124,7 @@ func LoadConfig() *Configuration {
 		}
 	})
 	if config.Model == "" {
-		config.DefaultMode = "gpt-3.5-turbo"
+		config.Model = "gpt-3.5-turbo"
 	}
 	if config.DefaultMode == "" {
 		config.DefaultMode = "单聊"