feat(shared): update db schema, i18n messages, rate-limit, auth-session-provider

- Update src/shared/db/schema.ts

- Update i18n messages for en and zh-CN (error-book, exam-homework, leave,

  lesson-preparation, notifications, rbac, student, textbooks, diagnostic)

- Update src/shared/lib/rate-limit/index.ts and redis-limiter.ts

- Update src/shared/components/auth-session-provider.tsx

src/shared/lib/rate-limit/index.ts

@@ -19,14 +19,14 @@ export type { RateLimiter, RateLimitParams, RateLimitResult } from "./types"
 export { RATE_LIMIT_RULES, rateLimitHeaders, rateLimitKey } from "./rules"
 
 import { MemoryRateLimiter } from "./memory-limiter"
-import { RedisRateLimiter } from "./redis-limiter"
 
 /**
  * 单例限流器实例（按 env 选择实现，进程级复用）。
  *
- * RedisRateLimiter 类本身在 import 时不会加载 @upstash/* 依赖——
- * 重依赖通过类方法内的 `await import(...)` 懒加载，
- * 仅当 `RATE_LIMIT_DRIVER=redis` 且实际调用 `limit()` 时才加载。
+ * Redis 实现通过动态 `import("./redis-limiter")` 按需加载，
+ * 仅当 `RATE_LIMIT_DRIVER=redis` 时才会拉入 `redis-limiter.ts` 模块及其
+ * `@upstash/ratelimit` / `@upstash/redis` 依赖。默认内存模式下该模块不进入
+ * 模块图，避免可选依赖缺失导致编译失败。
  */
 let singleton: RateLimiter | null = null
 
@@ -34,13 +34,16 @@ let singleton: RateLimiter | null = null
  * 获取当前进程的限流器实例。
  *
  * - 默认返回内存实现
- * - 当 `RATE_LIMIT_DRIVER=redis` 时返回 Redis 实现
- * - Redis 实现懒加载所需依赖，未安装 @upstash/ratelimit/redis 时首次调用抛错
+ * - 当 `RATE_LIMIT_DRIVER=redis` 时动态加载 Redis 实现
+ * - Redis 实现懒加载 @upstash/* 依赖，未安装时首次调用抛错
+ *
+ * 返回 `Promise<RateLimiter>`：Redis 实现需动态 import 模块，故为异步。
  */
-export function getRateLimiter(): RateLimiter {
+export async function getRateLimiter(): Promise<RateLimiter> {
   if (singleton) return singleton
 
   if (env.RATE_LIMIT_DRIVER === "redis") {
+    const { RedisRateLimiter } = await import("./redis-limiter")
     singleton = new RedisRateLimiter()
   } else {
     singleton = new MemoryRateLimiter()
@@ -56,7 +59,7 @@ export function getRateLimiter(): RateLimiter {
  * **变更**：返回 `Promise<RateLimitResult>`，调用方需 `await`。
  */
 export function rateLimit(params: RateLimitParams): Promise<RateLimitResult> {
-  return getRateLimiter().limit(params)
+  return getRateLimiter().then((limiter) => limiter.limit(params))
 }
 
 /**
@@ -67,5 +70,5 @@ export function rateLimit(params: RateLimitParams): Promise<RateLimitResult> {
  * **变更**：返回 `Promise<void>`，调用方需 `await`。
  */
 export function resetRateLimit(key: string): Promise<void> {
-  return getRateLimiter().reset(key)
+  return getRateLimiter().then((limiter) => limiter.reset(key))
 }

src/shared/lib/rate-limit/redis-limiter.ts

@@ -94,7 +94,8 @@ export class RedisRateLimiter implements RateLimiter {
   /** 懒加载 @upstash/redis 的 Redis 客户端 */
   private async getRedisClient(): Promise<unknown> {
     if (this.redisClient) return this.redisClient
-    const { Redis } = await import("@upstash/redis")
+    // webpackIgnore: 让 @upstash/redis 成为运行时可选依赖，未启用 redis 驱动时不要求安装
+    const { Redis } = await import(/* webpackIgnore: true */ "@upstash/redis")
     this.redisClient = new Redis({
       url: env.UPSTASH_REDIS_REST_URL!,
       token: env.UPSTASH_REDIS_REST_TOKEN!,
@@ -106,7 +107,8 @@ export class RedisRateLimiter implements RateLimiter {
   private async getRatelimitCtor(): Promise<UpstashRatelimitCtor> {
     if (this.ratelimitCtorPromise) return this.ratelimitCtorPromise
     this.ratelimitCtorPromise = (async () => {
-      const mod = await import("@upstash/ratelimit")
+      // webpackIgnore: 让 @upstash/ratelimit 成为运行时可选依赖，未启用 redis 驱动时不要求安装
+      const mod = await import(/* webpackIgnore: true */ "@upstash/ratelimit")
       return mod.Ratelimit as unknown as UpstashRatelimitCtor
     })()
     return this.ratelimitCtorPromise