REST Client: support download multiple files multipart/form-data

[comrt]

Description

Quarkus supports on server side multiple file downloads thanks to #26164

The new REST-Client allows multipart responses at the moment only with single files quarkus-rest-client.

In my use case i would like to download multiple files with the same content-disposition name to be generated as a list of Files or FileDownload like so:

public class FormDto {
  @RestForm 
  @PartType(MediaType.APPLICATION_OCTET_STREAM)
  public List<File> files;
  
  @RestForm 
  @PartType(MediaType.APPLICATION_OCTET_STREAM)
  public List<FileDownload> documents;
}

Implementation ideas

No response

[quarkus-bot]

/cc @cescoffier (rest-client), @geoand (rest-client)

[geoand]

#41982 takes care of it