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

package.json

@@ -5,7 +5,7 @@
   "type": "module",
   "scripts": {
     "dev": "bun --hot src/index.ts",
-    "build": "bun build src/index.ts --target=bun --outfile=dist/index.js && bun build src/db/migrate.ts --target=bun --outfile=dist/migrate.js",
+    "build": "bun build src/index.ts --target=bun --outfile=dist/index.js && bun build src/infrastructure/persistence/drizzle/migrate.ts --target=bun --outfile=dist/migrate.js",
     "start": "NODE_ENV=production bun dist/index.js",
     "db:migrate": "bun dist/migrate.js",
     "test": "bun test --preload ./test/helpers/setup-env.ts test/rateLimit.test.ts && bun test --preload ./test/helpers/setup-env.ts test/file.test.ts && bun test --preload ./test/helpers/setup-env.ts test/telegram.test.ts && bun test --preload ./test/helpers/setup-env.ts test/upload.test.ts && bun test --preload ./test/helpers/setup-env.ts test/files.test.ts && bun test --preload ./test/helpers/setup-env.ts test/health.test.ts && bun test --preload ./test/helpers/setup-env.ts test/db.test.ts &Line truncated