refactor: migrate backend framework from Express to NestJS

src/companies/companies.module.ts

@@ -0,0 +1,9 @@
+import { Module } from '@nestjs/common';
+import { CompaniesService } from './companies.service';
+import { CompaniesController } from './companies.controller';
+
+@Module({
+  controllers: [CompaniesController],
+  providers: [CompaniesService],
+})
+export class CompaniesModule {}