fix: code compliance audit and fix across all services

NestJS (6 services): implement @RequirePermission decorator with
SetMetadata+Reflector, register APP_GUARD globally, fix as assertions
to type guards, add explicit return types, fix import type for express,
fix /metrics implicit any, replace native Error with ApplicationError,
remove typeorm remnants, register LifecycleService.

teacher-bff: add logger, ApplicationError, GlobalErrorFilter, forward
real userId to downstream, log downstream failures, migrate health
controller to shared/health.

Go (2 services): interface to any, doc comments, CORS dev whitelist,
JWT secret fail-fast, push-gateway internal API auth, metrics and
readyz endpoints, remove dead code.

Python (2 services): lifespan return type, dev_mode to bool, data-ana
APIRouter, ai POST body model, ClickHouse async wrapping.

services/teacher-bff/package.json

@@ -30,6 +30,7 @@
     "@types/express": "^4.17.0",
     "@types/node": "^22.0.0",
     "eslint": "^9.10.0",
+    "pino-pretty": "^11.2.0",
     "typescript": "^5.6.0",
     "vitest": "^2.1.0"
   }