feat(task1): restructure directories for turborepo monorepo

- Move backend/ to apps/server/ via git mv
- Move frontend/ to apps/admin/ via git mv
- Create packages/typescript-config/ with base, nestjs, and react-vite presets

apps/server/src/main.ts

@@ -0,0 +1,13 @@
+import { NestFactory } from '@nestjs/core';
+import { ValidationPipe } from '@nestjs/common';
+import { AppModule } from './app.module';
+
+async function bootstrap() {
+  const app = await NestFactory.create(AppModule);
+  app.setGlobalPrefix('api');
+  app.enableCors();
+  app.useGlobalPipes(new ValidationPipe({ transform: true, whitelist: true }));
+  await app.listen(process.env.PORT ?? 3003);
+  console.log(`Server running on http://localhost:${process.env.PORT ?? 3003}`);
+}
+bootstrap();