task-56(账号/权限页面): 实现菜单编辑表单

menu-manage-model.ts 增 menuFormFromNode 回填 + menuParentChangeReason 防环(自身/子孙不可为父)；
menu-manage-api.ts 增 updateMenu PUT /api/admin/permission-menus/{id}；MenusPage 行内编辑复用
Dialog(新增/编辑切换)校验后提交并刷新。8 用例全过，411 单测 + build 绿。

admin-frontend-vue/src/pages/account/MenusPage.vue

@@ -1,10 +1,12 @@
 <script setup lang="ts">
 import { computed, onMounted, reactive, ref } from 'vue'
 import { ElMessage } from 'element-plus'
-import { createMenu, loadMenuManageTree } from './menu-manage-api'
+import { createMenu, loadMenuManageTree, updateMenu } from './menu-manage-api'
 import {
   createMenuForm,
   flattenMenuNodes,
+  menuFormFromNode,
+  menuParentChangeReason,
   nextSiblingSort,
   validateMenuManageForm,
   type MenuManageForm,
@@ -15,8 +17,10 @@ const loading = ref(false)
 const rows = ref<MenuManageNode[]>([])
 const createVisible = ref(false)
 const saving = ref(false)
+const editingNode = ref<MenuManageNode | null>(null)
 const menuForm = reactive<MenuManageForm>(createMenuForm(null, 0))
 const parentOptions = computed(() => flattenMenuNodes(rows.value))
+const dialogTitle = computed(() => (editingNode.value ? '编辑菜单' : '新增菜单'))
 
 async function loadMenus() {
   loading.value = true
@@ -30,11 +34,25 @@ async function loadMenus() {
 }
 
 function openCreate() {
+  editingNode.value = null
   Object.assign(menuForm, createMenuForm(null, nextSiblingSort(rows.value, null)))
   createVisible.value = true
 }
 
-async function saveCreate() {
+function openEdit(node: MenuManageNode) {
+  editingNode.value = node
+  Object.assign(menuForm, menuFormFromNode(node))
+  createVisible.value = true
+}
+
+async function saveMenu() {
+  if (editingNode.value) {
+    const reason = menuParentChangeReason(editingNode.value, menuForm.parentId)
+    if (reason) {
+      ElMessage.warning(reason)
+      return
+    }
+  }
   const { valid, errors } = validateMenuManageForm(menuForm)
   if (!valid) {
     ElMessage.warning(Object.values(errors)[0])
@@ -42,12 +60,17 @@ async function saveCreate() {
   }
   saving.value = true
   try {
-    await createMenu(menuForm)
-    ElMessage.success('创建成功')
+    if (editingNode.value) {
+      await updateMenu(editingNode.value.id, menuForm)
+      ElMessage.success('保存成功')
+    } else {
+      await createMenu(menuForm)
+      ElMessage.success('创建成功')
+    }
     createVisible.value = false
     await loadMenus()
   } catch (error) {
-    ElMessage.error(error instanceof Error ? error.message : '创建失败')
+    ElMessage.error(error instanceof Error ? error.message : '保存失败')
   } finally {
     saving.value = false
   }
@@ -72,14 +95,14 @@ onMounted(loadMenus)
         <el-table-column prop="routePath" label="路由" min-width="260" />
         <el-table-column prop="sortOrder" label="排序" width="100" />
         <el-table-column label="操作" width="140">
-          <template #default>
-            <el-button link type="primary">编辑</el-button>
+          <template #default="{ row }">
+            <el-button link type="primary" @click="openEdit(row)">编辑</el-button>
           </template>
         </el-table-column>
       </el-table>
     </el-card>
 
-    <el-dialog v-model="createVisible" title="新增菜单" width="520px">
+    <el-dialog v-model="createVisible" :title="dialogTitle" width="520px">
       <el-form label-width="96px">
         <el-form-item label="菜单名称">
           <el-input v-model="menuForm.name" placeholder="如：用户管理" />
@@ -106,7 +129,7 @@ onMounted(loadMenus)
       </el-form>
       <template #footer>
         <el-button @click="createVisible = false">取消</el-button>
-        <el-button type="primary" :loading="saving" @click="saveCreate">保存</el-button>
+        <el-button type="primary" :loading="saving" @click="saveMenu">保存</el-button>
       </template>
     </el-dialog>
   </div>