feat(admin): Admin V2 — Ant Design Pro 纯 SPA 重写

Next.js SSR/hydration 与 SWR fetch-on-mount 存在根本冲突：
hydration 卸载组件时 abort 的请求仍占用后端 DB 连接，
retry 循环耗尽 PostgreSQL 连接池导致后端完全卡死。

admin-v2 使用 Vite + React + antd 纯 SPA 彻底消除此问题：
- 12 页面全部完成（Login, Dashboard, Accounts, Providers, Models,
  API Keys, Usage, Relay, Config, Prompts, Logs, Agent Templates）
- ProTable + ProForm + ProLayout 统一 UI 模式
- TanStack Query + Axios + Zustand 数据层
- JWT 自动刷新 + 401 重试机制
- 全部 18 网络请求 200 OK，零 ERR_ABORTED

同时更新 troubleshooting 第 13 节和 SaaS 平台文档。

admin-v2/src/pages/Accounts.tsx

@@ -0,0 +1,170 @@
+// ============================================================
+// 账号管理
+// ============================================================
+
+import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query'
+import { Button, message, Tag, Modal, Form, Input, Select, Popconfirm, Space } from 'antd'
+import { PlusOutlined } from '@ant-design/icons'
+import type { ProColumns } from '@ant-design/pro-components'
+import { ProTable } from '@ant-design/pro-components'
+import { accountService } from '@/services/accounts'
+import type { AccountPublic } from '@/types'
+
+const roleLabels: Record<string, string> = {
+  super_admin: '超级管理员',
+  admin: '管理员',
+  user: '用户',
+}
+
+const roleColors: Record<string, string> = {
+  super_admin: 'red',
+  admin: 'blue',
+  user: 'default',
+}
+
+const statusLabels: Record<string, string> = {
+  active: '正常',
+  disabled: '已禁用',
+  suspended: '已封禁',
+}
+
+const statusColors: Record<string, string> = {
+  active: 'green',
+  disabled: 'default',
+  suspended: 'red',
+}
+
+export default function Accounts() {
+  const queryClient = useQueryClient()
+  const [form] = Form.useForm()
+  const [modalOpen, setModalOpen] = useState(false)
+  const [editingId, setEditingId] = useState<string | null>(null)
+
+  const { data, isLoading } = useQuery({
+    queryKey: ['accounts'],
+    queryFn: () => accountService.list(),
+  })
+
+  const updateMutation = useMutation({
+    mutationFn: ({ id, data }: { id: string; data: Partial<AccountPublic> }) =>
+      accountService.update(id, data),
+    onSuccess: () => {
+      message.success('更新成功')
+      queryClient.invalidateQueries({ queryKey: ['accounts'] })
+      setModalOpen(false)
+    },
+    onError: (err: Error) => message.error(err.message || '更新失败'),
+  })
+
+  const statusMutation = useMutation({
+    mutationFn: ({ id, status }: { id: string; status: AccountPublic['status'] }) =>
+      accountService.updateStatus(id, { status }),
+    onSuccess: () => {
+      message.success('状态更新成功')
+      queryClient.invalidateQueries({ queryKey: ['accounts'] })
+    },
+    onError: (err: Error) => message.error(err.message || '状态更新失败'),
+  })
+
+  const columns: ProColumns<AccountPublic>[] = [
+    { title: '用户名', dataIndex: 'username', width: 120 },
+    { title: '显示名', dataIndex: 'display_name', width: 120 },
+    { title: '邮箱', dataIndex: 'email', width: 180 },
+    {
+      title: '角色',
+      dataIndex: 'role',
+      width: 120,
+      render: (_, record) => <Tag color={roleColors[record.role]}>{roleLabels[record.role] || record.role}</Tag>,
+    },
+    {
+      title: '状态',
+      dataIndex: 'status',
+      width: 100,
+      render: (_, record) => <Tag color={statusColors[record.status]}>{statusLabels[record.status] || record.status}</Tag>,
+    },
+    {
+      title: '2FA',
+      dataIndex: 'totp_enabled',
+      width: 80,
+      render: (_, record) => record.totp_enabled ? <Tag color="green">已启用</Tag> : <Tag>未启用</Tag>,
+    },
+    {
+      title: '最后登录',
+      dataIndex: 'last_login_at',
+      width: 180,
+      render: (_, record) => record.last_login_at ? new Date(record.last_login_at).toLocaleString('zh-CN') : '-',
+    },
+    {
+      title: '操作',
+      width: 200,
+      render: (_, record) => (
+        <Space>
+          <Button size="small" onClick={() => { setEditingId(record.id); form.setFieldsValue(record); setModalOpen(true) }}>
+            编辑
+          </Button>
+          {record.status === 'active' ? (
+            <Popconfirm title="确定禁用此账号？" onConfirm={() => statusMutation.mutate({ id: record.id, status: 'disabled' })}>
+              <Button size="small" danger>禁用</Button>
+            </Popconfirm>
+          ) : (
+            <Popconfirm title="确定启用此账号？" onConfirm={() => statusMutation.mutate({ id: record.id, status: 'active' })}>
+              <Button size="small" type="primary">启用</Button>
+            </Popconfirm>
+          )}
+        </Space>
+      ),
+    },
+  ]
+
+  const handleSave = async () => {
+    const values = await form.validateFields()
+    if (editingId) {
+      updateMutation.mutate({ id: editingId, data: values })
+    }
+  }
+
+  return (
+    <div>
+      <ProTable<AccountPublic>
+        columns={columns}
+        dataSource={data?.items ?? []}
+        loading={isLoading}
+        rowKey="id"
+        search={false}
+        toolBarRender={() => []}
+        pagination={{
+          total: data?.total ?? 0,
+          pageSize: data?.page_size ?? 20,
+          current: data?.page ?? 1,
+          showSizeChanger: false,
+        }}
+      />
+
+      <Modal
+        title="编辑账号"
+        open={modalOpen}
+        onOk={handleSave}
+        onCancel={() => { setModalOpen(false); setEditingId(null); form.resetFields() }}
+        confirmLoading={updateMutation.isPending}
+      >
+        <Form form={form} layout="vertical">
+          <Form.Item name="display_name" label="显示名">
+            <Input />
+          </Form.Item>
+          <Form.Item name="email" label="邮箱">
+            <Input type="email" />
+          </Form.Item>
+          <Form.Item name="role" label="角色">
+            <Select options={[
+              { value: 'super_admin', label: '超级管理员' },
+              { value: 'admin', label: '管理员' },
+              { value: 'user', label: '用户' },
+            ]} />
+          </Form.Item>
+        </Form>
+      </Modal>
+    </div>
+  )
+}
+
+import { useState } from 'react'