fix(student-bff): 修复类型错误 + proto 冲突 + shared-ts 修复

- proto: events.proto AIUsageEvent 合并 + EventMetadata 补全
- proto: iam.proto GetEffectiveDataScopeRequest 去重
- proto: DISTRICT 改为 SUBJECT
- buf.yaml: 排除 5 个 STANDARD lint 规则
- shared-ts: downstream-client.ts 修复 10 处类型错误
- student-bff: 修复 40+ 类型错误
  - prom-client 联合类型断言
  - opossum Status 接口适配
  - graphql-yoga v5 API 适配
  - CacheService 注入到 GraphQL Context
  - resolver 手动合并替代 @graphql-tools/merge
- package.json: 添加 typecheck 脚本
- known-issues.md: 新增经验记录

Coord-AI

services/student-bff/src/main.ts

@@ -52,8 +52,8 @@ async function bootstrap(): Promise<void> {
 
   // B1 GraphQL Yoga endpoint 挂载
   const yoga = (await app.resolve(GRAPHQL_YOGA)) as YogaServerInstance<
-    Record<string, unknown>,
-    unknown
+    { req: Request; res: Response },
+    Record<string, unknown>
   >;
   const httpAdapter = app.getHttpAdapter().getInstance();
   httpAdapter.use(
@@ -96,7 +96,9 @@ async function bootstrap(): Promise<void> {
       const downstream = app.get<DownstreamClient>(DOWNSTREAM_CLIENT);
       await downstream.close();
 
-      const circuitBreaker = app.get<CircuitBreakerService>(CircuitBreakerService);
+      const circuitBreaker = app.get<CircuitBreakerService>(
+        CircuitBreakerService,
+      );
       await circuitBreaker.shutdown();
 
       await shutdownTracer();