零 Node 部署、超级管理员，并完善本地构建发布文档。

- FastAPI 单进程托管 frontend/dist，systemd 替代 PM2

- 超级管理员 admin、注册开关与用户管理

- README/DEPLOY/USAGE 说明：改代码须本地构建 dist 后 push，服务器 update.sh

- 提交 frontend/dist 与 build-frontend 脚本

frontend/src/api/client.ts

@@ -1,10 +1,13 @@
 import axios from 'axios'
 import type {
+  AdminUser,
   Exam,
+  PublicSettings,
   ScoreInput,
   SchoolLevel,
   Student,
   Subject,
+  SystemSettings,
   TokenResponse,
   TrendResponse,
   User,
@@ -59,6 +62,27 @@ export const authApi = {
   me: () => api.get<User>('/auth/me'),
 }
 
+export const settingsApi = {
+  public: () => api.get<PublicSettings>('/settings/public'),
+}
+
+export const adminApi = {
+  getSettings: () => api.get<SystemSettings>('/admin/settings'),
+  updateSettings: (data: { registration_enabled?: boolean }) =>
+    api.patch<SystemSettings>('/admin/settings', data),
+  updateProfile: (data: {
+    username?: string
+    current_password?: string
+    password?: string
+  }) => api.patch<AdminUser>('/admin/profile', data),
+  listUsers: () => api.get<AdminUser[]>('/admin/users'),
+  createUser: (data: { username: string; password: string }) =>
+    api.post<AdminUser>('/admin/users', data),
+  resetUserPassword: (id: string, password: string) =>
+    api.patch<AdminUser>(`/admin/users/${id}`, { password }),
+  deleteUser: (id: string) => api.delete(`/admin/users/${id}`),
+}
+
 export const studentApi = {
   list: () => api.get<Student[]>('/students'),
   create: (data: {