feat: 支持注销用户并展示普通用户使用情况

- 新增管理员注销用户接口，要求输入用户名二次确认
- 注销时清理用户当前图片、视频、文件、标签、会话和自身日志
- 保留备份任务、管理员审计数据和全局配置
- 用户列表展示图片、视频、文件占用，管理员行隐藏使用情况和操作按钮
- 补充注销流程与用量统计测试

app/pages/users.vue

@@ -1,10 +1,17 @@
 <script setup lang="ts">
+import { formatFileSize } from '~/composables/useFileSize'
+
 interface AdminUser {
   id: number
   username: string
   role: 'admin' | 'user'
   created_at: string
   password_reset: number
+  usage?: {
+    imageBytes: number
+    videoBytes: number
+    fileBytes: number
+  }
 }
 
 const {
@@ -21,6 +28,18 @@ const { t } = useI18n()
 
 const users = ref<AdminUser[]>([])
 const loading = ref(false)
+const deleteTarget = ref<AdminUser | null>(null)
+const deleteConfirm = ref('')
+const deleting = ref(false)
+
+const canDelete = computed(() =>
+  Boolean(
+    deleteTarget.value
+    && deleteTarget.value.role !== 'admin'
+    && deleteConfirm.value.trim() === deleteTarget.value.username
+    && !deleting.value
+  )
+)
 
 async function loadUsers() {
   if (!isAdmin.value) return
@@ -57,6 +76,51 @@ async function clearPassword(user: AdminUser) {
   }
 }
 
+function openDeleteDialog(user: AdminUser) {
+  if (user.role === 'admin') return
+  deleteTarget.value = user
+  deleteConfirm.value = ''
+}
+
+function closeDeleteDialog() {
+  if (deleting.value) return
+  deleteTarget.value = null
+  deleteConfirm.value = ''
+}
+
+function onDeleteOpenChange(open: boolean) {
+  if (!open) closeDeleteDialog()
+}
+
+async function deleteUser() {
+  const target = deleteTarget.value
+  if (!target || !canDelete.value) return
+
+  deleting.value = true
+  try {
+    await $fetch(`/api/admin/users/${target.id}/delete`, {
+      method: 'POST',
+      credentials: 'include',
+      body: { confirmation: deleteConfirm.value.trim() }
+    })
+    toast.add({
+      title: t('users.userDeleted', { name: target.username }),
+      color: 'success'
+    })
+    deleteTarget.value = null
+    deleteConfirm.value = ''
+    await loadUsers()
+  } catch (error: unknown) {
+    handleAuthError(error)
+    toast.add({
+      title: getFetchErrorMessage(error, t('users.deleteFailed')),
+      color: 'error'
+    })
+  } finally {
+    deleting.value = false
+  }
+}
+
 function formatDate(value: string) {
   try {
     return new Date(value).toLocaleString()
@@ -150,24 +214,83 @@ onMounted(async () => {
             </p>
           </div>
 
-          <UBadge
-            v-if="user.password_reset === 1"
-            color="warning"
-            variant="subtle"
-            size="sm"
+          <div
+            v-if="user.role !== 'admin'"
+            class="flex flex-wrap items-center gap-x-3 gap-y-1 text-xs text-muted"
           >
-            {{ t('users.resetPending') }}
-          </UBadge>
-          <UButton
-            v-else
-            variant="outline"
-            color="warning"
-            size="sm"
-            :label="t('users.clearPassword')"
-            @click="clearPassword(user)"
-          />
+            <span>{{ t('users.usageImages') }} {{ formatFileSize(user.usage?.imageBytes ?? 0) }}</span>
+            <span>{{ t('users.usageVideos') }} {{ formatFileSize(user.usage?.videoBytes ?? 0) }}</span>
+            <span>{{ t('users.usageFiles') }} {{ formatFileSize(user.usage?.fileBytes ?? 0) }}</span>
+          </div>
+          <div
+            v-if="user.role !== 'admin'"
+            class="flex items-center gap-2"
+          >
+            <UBadge
+              v-if="user.password_reset === 1"
+              color="warning"
+              variant="subtle"
+              size="sm"
+            >
+              {{ t('users.resetPending') }}
+            </UBadge>
+            <UButton
+              v-if="user.password_reset !== 1"
+              variant="outline"
+              color="warning"
+              size="sm"
+              :label="t('users.clearPassword')"
+              @click="clearPassword(user)"
+            />
+            <UButton
+              variant="outline"
+              color="error"
+              size="sm"
+              :label="t('users.deleteUser')"
+              @click="openDeleteDialog(user)"
+            />
+          </div>
         </li>
       </ul>
     </AppShell>
+
+    <UModal
+      :open="Boolean(deleteTarget)"
+      :title="t('users.deleteTitle')"
+      :description="t('users.deleteWarning')"
+      @update:open="onDeleteOpenChange"
+    >
+      <template #body>
+        <div class="space-y-2">
+          <p class="text-sm text-muted">
+            {{ t('users.deleteConfirmLabel', { name: deleteTarget?.username ?? '' }) }}
+          </p>
+          <UInput
+            v-model="deleteConfirm"
+            :placeholder="deleteTarget?.username"
+            class="w-full"
+            autocomplete="off"
+          />
+        </div>
+      </template>
+      <template #footer>
+        <div class="flex justify-end gap-2">
+          <UButton
+            :label="t('common.cancel')"
+            color="neutral"
+            variant="outline"
+            :disabled="deleting"
+            @click="closeDeleteDialog"
+          />
+          <UButton
+            :label="t('users.deleteSubmit')"
+            color="error"
+            :loading="deleting"
+            :disabled="!canDelete"
+            @click="deleteUser"
+          />
+        </div>
+      </template>
+    </UModal>
   </div>
 </template>