chore: configure angular and postgres foundation

apps/api/src/database/data-source.ts

@@ -0,0 +1,16 @@
+import 'dotenv/config';
+import { DataSource } from 'typeorm';
+
+const databaseUrl = process.env.DATABASE_URL;
+
+if (!databaseUrl?.trim()) {
+  throw new Error('DATABASE_URL is required');
+}
+
+export const AppDataSource = new DataSource({
+  type: 'postgres',
+  url: databaseUrl,
+  entities: [__dirname + '/../**/*.entity.{ts,js}'],
+  migrations: [__dirname + '/migrations/*.{ts,js}'],
+  synchronize: false,
+});