fix: prevent empty category validation request

src/views/assessment/optimization.vue

@@ -238,11 +238,17 @@ async function persistProgress(saveAction = "SAVE") { await saveStudentTrainingA
 function addRow() { if (categoryRows.value.length >= MAX_ROWS) return; categoryRows.value.push(createRow()); }
 function removeLastRow() { categoryRows.value.pop(); }
 async function validateStepOne() {
+  if (!categoryRows.value.length) {
+    ElMessage.warning("请至少填写一行品类数据");
+    return false;
+  }
   try {
     const response = await validateCategoryOptimizationStepOne({ rows: categoryRows.value });
     if (response?.data?.valid === false) throw new Error(response.data.message || "数据校验未通过");
     return true;
   } catch (error) {
+    // 请求层已经展示了后端 400 返回的业务提示，避免再叠加一条英文 Axios 错误。
+    if (error?.response?.status === 400) return false;
     ElMessage.error(error?.message || error?.msg || "数据校验未通过，请检查填写内容");
     return false;
   }