Transport.NATS for NESTjs fine creds launching

Question

Try to create "Hybrid app" REST + NATS from official docs: https://docs.nestjs.com/faq/hybrid-application

but

1. if add cred options like

authentiacator: credsAuthenticator(new TextEncoder().encode(creds)),

in two place, both in main.ts:

async function bootstrap() {
  const app = await NestFactory.create(AppModule, {cors: true});
  const microService = await app.connectMicroservice({
    transport: Transport.NATS,
    options: {/* ... */} 
  })
  await microService.listen();
  await app.listen();
//...

• and in app.module.ts:

@Module({
  imports: [
    ClientsModule.register([{
      transport: Transport.NATS,
      options: //...

The docker detail logs twice authenticate calls

2. if cred placed only single place

• app throwing "NatsError: 'Authorization Violation'"

3. if in app.module not add ClientsModule.register at all

• not working DI

4. if in main.ts not add connectMicroservice({...}).listen() at all

• it runs without error, and in controller works .client.emit(pattern, data) (and NATS log one Authentication message) but @MessagePattern receiving not working at all. (The oposite side logs that no responders)

So... how to deduplicate options creds (and most important: deduplicate twice authenticating)
Or it exact really that was right?

Upd: Part of solution to deduplicate code is by adding ClientsModule.registerAsync to app.module.ts and Configurer.getNatsConfig to main.ts:

// configure.root.ts
export class Configurer {
    static getNatsConfig(configService?: ConfigService){
        let servers = configService?.get<string>('NATS') ?? process.env.S_AVE_NATS;
        // process.env fallback to early direct call Configurer.getNatsConfig(undefined)
        return {
            transport: Transport.NATS,
            options: {
                servers: servers.split(' '),
                authenticator: credsAuthenticator(new TextEncoder().encode(stringOfNatsUserCredsFile)),
                name: 'service-subscriber',
            }
        }
    }, // ...
}
// async launcher
export const natsConfigAsync: any = [{
    name: 'NATS',
    imports: [ConfigModule],
    inject: [ConfigService],
    useFactory: async (configService: ConfigService) =>
        (Configurer.getNatsConfig(configService))
}]

// main.ts
async function bootstrap() {
  const app = await NestFactory.create(AppModule, { cors: true });
  await app.connectMicroservice({
    name: 'S_AVE',
    ... Configurer.getNatsConfig(),
  });
  await app.startAllMicroservices();  
  let server = await app.listen(process.env.PORT || 3000);
  console.log(`serve on port: ${process.env.PORT || 3000}`);
}
bootstrap();

// app.module.ts
@Module({
  imports: [
    ConfigModule.forRoot({ isGlobal: true, envFilePath: `.env.${process.env.NODE_ENV || 'development'}`}),
    TypeOrmModule.forRootAsync(typeOrmConfigAsync),
    TypeOrmModule.forFeature([UserEntity]),
    ClientsModule.registerAsync(natsConfigAsync), // TODO: Fix duplicate connection
    AuthModule,
  ],
  controllers: [AppController],
  providers: [AppService],
})
export class AppModule {}

• but it still twice create connection (by the NATS log)