refactor: full DDD + Clean Architecture refactor

- Hapus src/utils/ (17 files) + src/db/ (8 files) dead code
- Absorb 7 re-export stubs → real impl di lokasi DDD
- Buat src/infrastructure/di.ts (DI container)
- Rewrite 5 controllers pakai repository/DI
- Fix shared/utils imports, env.ts, routes, index.ts
- Update package.json build path migrate
- Lint clean, build clean

src/env.ts

@@ -1,4 +1,4 @@
-import logger from './utils/logger';
+import logger from './shared/logger/index';
 
 interface AppConfig {
   /** All bot tokens merged from BOT_TOKENS (or BOT_TOKEN + ADDITIONAL_BOT_TOKENS fallback) */