Monitoring and health checks

this.logger.log('Order approved: ' + orderId);
this.logger.warn('Rate limit exceeded for client: ' + clientId);
this.logger.error('Failed to send email: ' + error.message);

GET /api/v1/health

{
  "status": "ok",
  "timestamp": "2026-09-04T12:00:00.000Z",
  "uptime": 86400
}

@Controller('health')
export class HealthController {
  @Get()
  check() {
    return {
      status: 'ok',
      timestamp: new Date().toISOString(),
      uptime: process.uptime(),
    };
  }
}