add NestJS skeleton and GET /api/health-check.

Thin API bootstrap with config module and nullcart-style health route for Docker checks.

backend/src/modules/healthCheck/controllers/HealthCheckController.ts

@@ -0,0 +1,10 @@
+import { Controller, Get, HttpStatus, Res } from '@nestjs/common';
+import type { Response } from 'express';
+
+@Controller('/health-check')
+export class HealthCheckController {
+    @Get('/')
+    getStatus(@Res() res: Response) {
+        return res.sendStatus(HttpStatus.OK);
+    }
+}