fix(llm): 修复微调保存步数默认值逻辑

- 使用 Optional.ofNullable() 处理 fineTuningTask.getSaveSteps() 的值
- 在原值基础上加 1，确保保存步数至少为 1
- 优化了代码的可读性和健壮性

yudao-module-llm/yudao-module-llm-biz/src/main/java/cn/iocoder/yudao/module/llm/service/async/AsyncFineTuningTaskService.java

@@ -177,7 +177,9 @@ public class AsyncFineTuningTaskService {
         AigcFineTuningCreateReqVO req = new AigcFineTuningCreateReqVO();
         req.setModel(fineTuningTask.getBaseModel());
         req.setTrainEpoch((fineTuningTask.getEpoch() == 0) ? 1 : fineTuningTask.getEpoch());
-        req.setTrainEpoch((fineTuningTask.getSaveSteps() == 0) ? 1 : fineTuningTask.getSaveSteps());
+        int saveStep = Optional.ofNullable(fineTuningTask.getSaveSteps())
+                                     .orElse(0) + 1;
+        req.setTrainEpoch(saveStep);
         req.setSuffix(fineTuningTask.getTaskName());
         req.setRemark(fineTuningTask.getTaskIntro());
         req.setTrainBatchSize(fineTuningTask.getBatchSize());