task-52(账号/权限页面): 实现用户列表加载/空/错状态

新增 user-list-state.ts 纯 phase 归一(loading>error>empty>ready)与空/错提示；
UsersPage 显式 loadError 态 + 错误 el-alert(带重试)、加载/错误/空相位决策、
删除按钮对超管禁用。8 用例全过，379 单测 + build 绿。

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

@@ -1,19 +1,23 @@
 <script setup lang="ts">
-import { onMounted, reactive, ref } from 'vue'
+import { computed, onMounted, reactive, ref } from 'vue'
 import { ElMessage, ElMessageBox } from 'element-plus'
 import type { AdminUser } from '@/types/admin'
 import { deleteUser, fetchUserList } from '@/api/users'
 import { createUserFilterState, toUserListParams } from './users-filter'
 import { totalPageCount } from './user-pagination'
 import { deleteBlockReason } from './user-delete-model'
+import { listPhaseOf } from './user-list-state'
 
 const loading = ref(false)
+const loadError = ref('')
 const rows = ref<AdminUser[]>([])
 const total = ref(0)
 const filters = reactive(createUserFilterState())
+const statePhase = computed(() => listPhaseOf({ loading: loading.value, error: loadError.value, items: rows.value, total: total.value }))
 
 async function loadUsers() {
   loading.value = true
+  loadError.value = ''
   try {
     const page = await fetchUserList(toUserListParams(filters))
     rows.value = page.items
@@ -27,12 +31,18 @@ async function loadUsers() {
       total.value = retried.total
     }
   } catch (error) {
-    ElMessage.error(error instanceof Error ? error.message : '用户列表加载失败')
+    loadError.value = error instanceof Error ? error.message : '用户列表加载失败'
+    ElMessage.error(loadError.value)
   } finally {
     loading.value = false
   }
 }
 
+/** 错误态重试：重新拉取当前筛选列表。 */
+function retry() {
+  void loadUsers()
+}
+
 /** 提交新筛选条件：重置回第一页再查询。 */
 function search() {
   filters.page = 1
@@ -83,6 +93,18 @@ onMounted(loadUsers)
       </el-form>
     </el-card>
     <el-card shadow="never">
+      <el-alert
+        v-if="statePhase === 'error' && loadError"
+        :title="loadError"
+        type="error"
+        show-icon
+        :closable="false"
+        style="margin-bottom: 12px"
+      >
+        <template #default>
+          <el-button link type="primary" @click="retry">重试</el-button>
+        </template>
+      </el-alert>
       <el-table v-loading="loading" :data="rows" stripe>
         <el-table-column prop="id" label="ID" width="90" />
         <el-table-column prop="username" label="用户名" min-width="180" />
@@ -91,7 +113,7 @@ onMounted(loadUsers)
         <el-table-column prop="createdAt" label="创建时间" width="180" />
         <el-table-column label="操作" width="120" fixed="right">
           <template #default="{ row }">
-            <el-button link type="danger" @click="removeUser(row)">删除</el-button>
+            <el-button link type="danger" :disabled="deleteBlockReason(row) !== undefined" @click="removeUser(row)">删除</el-button>
           </template>
         </el-table-column>
       </el-table>

admin-frontend-vue/src/pages/account/user-list-state.ts

@@ -0,0 +1,31 @@
+/** 用户列表加载/空/错状态（任务 52）：纯 phase 归一无 UI 依赖，供页面展示决策复用。 */
+
+export type ListPhase = 'loading' | 'error' | 'empty' | 'ready'
+
+export interface UserListPhaseInput {
+  loading?: boolean
+  error?: string
+  items?: unknown[]
+  total?: number
+}
+
+/** 归一列表展示相位：loading 优先，其次 error，其次空，否则 ready。 */
+export function listPhaseOf(input: UserListPhaseInput): ListPhase {
+  if (input.loading) return 'loading'
+  if (typeof input.error === 'string' && input.error.trim()) return 'error'
+  const items = Array.isArray(input.items) ? input.items : []
+  const total = typeof input.total === 'number' ? input.total : items.length
+  if (items.length === 0 || total === 0) return 'empty'
+  return 'ready'
+}
+
+/** 空态提示文案。 */
+export function userListEmptyHint(): string {
+  return '暂无用户数据'
+}
+
+/** 错误态可操作提示：带上具体原因，缺省给通用文案。 */
+export function userListErrorHint(message?: string | null): string {
+  const text = (message || '').trim()
+  return text ? `加载失败：${text}` : '加载失败，请稍后重试'
+}