add TypeORM postgres config and migration runner.

backend/src/main.ts

@@ -2,13 +2,13 @@ import { ValidationPipe } from '@nestjs/common';
 import { ConfigService } from '@nestjs/config';
 import { NestFactory } from '@nestjs/core';
 import { AppModule } from './AppModule';
-import { AppConfig } from './types/AppConfig';
+import { Config } from './types/Config';
 
 async function bootstrap() {
     const app = await NestFactory.create(AppModule);
 
     const configService = app.get(ConfigService);
-    const { port, corsOrigins } = configService.get('app') as AppConfig;
+    const { port, corsOrigins } = configService.get('app') as Config['app'];
 
     app.setGlobalPrefix('api');