Misleading naming: FilesS3PresignedModule implements server-side streaming (Multer) instead of Presigned URLs

[hankaibo]

Describe the bug
I noticed that the module named FilesS3PresignedModule (and its corresponding service/controller) is not actually implementing a "Presigned URL" strategy.

Instead, it is using MulterModule with multer-s3. This setup implements a server-side streaming upload strategy, where the client sends the file to the NestJS server, and the server proxies it to S3.

To Reproduce
Check the FilesS3PresignedModule configuration:

@Module({
  imports: [
    // ...
    MulterModule.registerAsync({
      // ...
      useFactory: (configService: ConfigService<AllConfigType>) => {
        return {
          // This indicates a server-side upload via Multer middleware
          storage: multerS3({
            s3: s3,
            bucket: '',
            // ...
          }),
        };
      },
    }),
  ],
  // ...
})
export class FilesS3PresignedModule {}

Expected behavior
A module named "Presigned" implies a Client-Side Direct Upload strategy.

The client requests an upload URL.

The backend generates a pre-signed URL (using getSignedUrl or signatureUrl) and returns it as JSON.

The client uploads the file directly to S3/OSS.

Multer should not be involved in a presigned flow because the file binary data never touches the backend API.