fix(ui-cases): 修复步骤表格不显示定位信息问题

- Cases.vue 新增"定位类型"和"定位值"两列
- 兼容多种命名格式（locatorType/locator_type/params.selector）
- formatParams 排除 selector 字段避免重复显示
- element_locator.py 批量定位同时写入驼峰和蛇形命名
- 新增批量获取定位按钮（绿色），一键获取用例所有步骤定位
Co-Authored-By: Claude <noreply@anthropic.com>

frontend/src/views/Cases.vue

@@ -176,7 +176,7 @@
             {{ formatTime(row.created_at) }}
           </template>
         </el-table-column>
-        <el-table-column label="操作" width="200" fixed="right">
+        <el-table-column label="操作" width="280" fixed="right">
           <template #default="{ row }">
             <el-button size="small" type="primary" link @click="showEditDialog(row)">
               编辑
@@ -184,6 +184,16 @@
             <el-button size="small" type="primary" link @click="viewCaseDetail(row)">
               查看
             </el-button>
+            <el-button
+              size="small"
+              type="success"
+              link
+              @click="batchLocate(row)"
+              :loading="locatingCaseId === row.id"
+              :disabled="row.caseType !== 'ui'"
+            >
+              获取定位
+            </el-button>
             <el-button size="small" type="warning" link @click="copyCase(row)">
               复制
             </el-button>
@@ -361,13 +371,36 @@
             v-if="currentCase.steps && currentCase.steps.length > 0"
           >
             <el-table-column label="#" width="50" type="index" />
-            <el-table-column label="步骤名称" prop="name" min-width="150" />
-            <el-table-column label="动作" width="100">
+            <el-table-column label="步骤名称" prop="name" min-width="120" />
+            <el-table-column label="动作" width="90">
               <template #default="{ row }">
                 <el-tag size="small" effect="plain">{{ row.action }}</el-tag>
               </template>
             </el-table-column>
-            <el-table-column label="参数" min-width="200">
+            <el-table-column label="定位类型" width="100">
+              <template #default="{ row }">
+                <el-tag
+                  v-if="row.locatorType || row.locator_type"
+                  size="small"
+                  type="success"
+                >
+                  {{ row.locatorType || row.locator_type }}
+                </el-tag>
+                <span v-else class="text-gray">-</span>
+              </template>
+            </el-table-column>
+            <el-table-column label="定位值" min-width="180">
+              <template #default="{ row }">
+                <code
+                  v-if="row.locatorValue || row.locator_value || row.params?.selector"
+                  class="locator-code"
+                >
+                  {{ row.locatorValue || row.locator_value || row.params?.selector }}
+                </code>
+                <span v-else class="text-gray">-</span>
+              </template>
+            </el-table-column>
+            <el-table-column label="参数" min-width="150">
               <template #default="{ row }">
                 <span class="params-text">{{ formatParams(row.params) }}</span>
               </template>
@@ -493,6 +526,7 @@ import {
 import { caseApi } from '@/api/cases'
 import { moduleApi, buildModuleTree } from '@/api/modules'
 import { executionApi } from '@/api/executions'
+import { elementLocateApi } from '@/api/elementLocate'
 import CaseStepEditor from '@/components/CaseStepEditor.vue'
 import IntentStepEditor from '@/components/IntentStepEditor.vue'
 import { toStepDefinition, toIntentStep } from '@/utils/stepParser'
@@ -689,7 +723,11 @@ const formatParams = (params: any) => {
   if (!params) return '-'
   if (typeof params === 'string') return params
   try {
-    return JSON.stringify(params)
+    // 排除 selector（已在定位值列单独显示）
+    const { selector, ...rest } = params
+    const keys = Object.keys(rest)
+    if (keys.length === 0) return '-'
+    return JSON.stringify(rest)
   } catch {
     return '-'
   }
@@ -841,6 +879,57 @@ const deleteCase = async (row: any) => {
   }
 }
 
+// ==================== 批量获取定位 ====================
+
+/** 当前正在获取定位的用例 ID */
+const locatingCaseId = ref('')
+
+/**
+ * 一键获取用例所有步骤的元素定位
+ *
+ * 流程：
+ * 1. 调用批量定位 API
+ * 2. 后端启动 Playwright → 登录 → 访问页面 → 提取元素
+ * 3. 为每个步骤匹配定位器并更新到数据库
+ * 4. 前端显示结果
+ */
+const batchLocate = async (row: any) => {
+  try {
+    await ElMessageBox.confirm(
+      `将为用例「${row.name}」的所有步骤自动获取元素定位，是否继续？`,
+      '批量获取定位',
+      { type: 'info', confirmButtonText: '开始获取', cancelButtonText: '取消' }
+    )
+  } catch {
+    return
+  }
+
+  locatingCaseId.value = row.id
+  try {
+    ElMessage.info('正在启动浏览器获取定位，请稍候...')
+
+    const result = await elementLocateApi.locateBatch({
+      case_id: row.id,
+      page_url: 'https://192.168.5.44/',
+      auto_login: true,
+    })
+
+    if (result.success) {
+      const msg = `定位完成：成功 ${result.located_steps}/${result.total_steps} 个步骤`
+      ElMessage.success(msg)
+
+      // 刷新用例列表
+      await loadCases()
+    } else {
+      ElMessage.warning(result.message || '定位失败')
+    }
+  } catch (error: any) {
+    ElMessage.error('批量定位失败: ' + (error.message || '未知错误'))
+  } finally {
+    locatingCaseId.value = ''
+  }
+}
+
 const runSelectedCases = async () => {
   if (selectedCases.value.length === 0) return
 
@@ -1032,6 +1121,19 @@ onMounted(() => {
         color: #909399;
         word-break: break-all;
       }
+
+      .locator-code {
+        font-family: 'Consolas', 'Monaco', monospace;
+        font-size: 11px;
+        background: #f5f7fa;
+        padding: 2px 6px;
+        border-radius: 3px;
+        color: #409eff;
+        display: inline-block;
+        max-width: 100%;
+        overflow: hidden;
+        text-overflow: ellipsis;
+      }
     }
   }