feat: 班级小助手 阶段1-3（monorepo + 后端 REST/Socket.IO + Web 管理端）

packages/shared/src/constants.ts

@@ -0,0 +1,108 @@
+import type { NotificationPriority, UserRole } from './types.js';
+
+/** API 前缀 */
+export const API_PREFIX = '/api';
+
+/** REST 路径集中管理，避免前端散落硬编码字符串 */
+export const API_PATHS = {
+  auth: {
+    login: '/auth/login',
+    logout: '/auth/logout',
+    me: '/auth/me',
+    changePassword: '/auth/password',
+  },
+  classes: '/classes',
+  courses: '/courses',
+  schedules: '/schedules',
+  homeworks: '/homeworks',
+  notifications: '/notifications',
+  grades: '/grades',
+  students: '/students',
+  teachers: '/teachers',
+  dashboard: '/dashboard/summary',
+} as const;
+
+/** 用户角色 */
+export const USER_ROLES: readonly UserRole[] = ['ADMIN', 'TEACHER', 'STUDENT'];
+
+export const ROLE_LABELS: Record<UserRole, string> = {
+  ADMIN: '系统管理员',
+  TEACHER: '教师',
+  STUDENT: '学生',
+};
+
+/** 通知优先级 */
+export const NOTIFICATION_PRIORITIES: readonly NotificationPriority[] = ['LOW', 'NORMAL', 'HIGH', 'URGENT'];
+
+export const PRIORITY_LABELS: Record<NotificationPriority, string> = {
+  LOW: '低',
+  NORMAL: '普通',
+  HIGH: '重要',
+  URGENT: '紧急',
+};
+
+/** Element Plus tag 类型，三端统一文案与配色 */
+export const PRIORITY_TAG_TYPES: Record<NotificationPriority, 'info' | 'primary' | 'warning' | 'danger'> = {
+  LOW: 'info',
+  NORMAL: 'primary',
+  HIGH: 'warning',
+  URGENT: 'danger',
+};
+
+/** 星期：1=周一 ... 7=周日（与数据库 dayOfWeek 一致） */
+export const WEEKDAY_LABELS: Record<number, string> = {
+  1: '周一',
+  2: '周二',
+  3: '周三',
+  4: '周四',
+  5: '周五',
+  6: '周六',
+  7: '周日',
+};
+
+export const WEEKDAYS: readonly number[] = [1, 2, 3, 4, 5, 6, 7];
+
+/** 默认学期周次上限 */
+export const DEFAULT_WEEK_COUNT = 20;
+
+/** WebSocket 事件名（服务端广播 / 客户端监听保持一致） */
+export const SOCKET_EVENTS = {
+  notificationNew: 'notification:new',
+  homeworkNew: 'homework:new',
+  homeworkUpdated: 'homework:updated',
+  homeworkStatus: 'homework:status',
+  gradeUpdated: 'grade:updated',
+  scheduleUpdated: 'schedule:updated',
+  classUpdated: 'class:updated',
+  connected: 'connected',
+} as const;
+
+/** Socket.IO 房间名生成规则：与后端保持一致，客户端订阅时复用 */
+export const SOCKET_ROOMS = {
+  class: (classId: string): string => `class:${classId}`,
+  user: (userId: string): string => `user:${userId}`,
+  teacher: (teacherId: string): string => `teacher:${teacherId}`,
+  role: (role: UserRole): string => `role:${role}`,
+  students: 'students',
+  teachers: 'teachers',
+} as const;
+
+/** 本地持久化键（Web 端 localStorage / EXE 端 IndexedDB 命名空间） */
+export const STORAGE_KEYS = {
+  token: 'classhelper.token',
+  user: 'classhelper.user',
+  serverUrl: 'classhelper.serverUrl',
+  cachePrefix: 'classhelper.cache',
+  lastSyncAt: 'classhelper.lastSyncAt',
+} as const;
+
+/** 桌面客户端默认后端地址 */
+export const DEFAULT_SERVER_URL = 'http://127.0.0.1:4000';
+
+/** 默认端口与分页 */
+export const DEFAULT_SERVER_PORT = 4000;
+export const DEFAULT_PAGE_SIZE = 20;
+export const MAX_PAGE_SIZE = 200;
+
+/** 教师与管理员角色集合，便于 RBAC 判断 */
+export const STAFF_ROLES: readonly UserRole[] = ['ADMIN', 'TEACHER'];