Feature Request/431 file upload page missing features

Overview of the Feature Request
This issue summarizes the remaining work needed to have a fully featured file upload functionality in the new SPA UI.
Follow-up to the PR #418:

• #481
• use the new SelectMultiple component for tag selection
• implement handling of the duplicate files having either an identical content or label+name
• extend the interface of the add uploaded files call in the js-dataverse library to accept more parameters, like tags, description, etc., and make it support adding multiple files at once, i.s.o. adding files one-by-one (addUploadedFilesToDataset call), see also https://guides.dataverse.org/en/latest/developers/s3-direct-upload-api.html#direct-add-to-dataset-api. When ready, the implementation of FileJSDataverseRepository.ts addUploadedFile method can be refactored to no longer mock a file, that is not needed here, but to use a proper interface with description, restricted boolean, tags, etc.
• implement turning off tagging option for the file upload use case in DV-JS client
• implement new use case needed for installations not supporting S3 tagging, but also useful for other installations: cleanup storage of a dataset
• refactor scss of src/sections/upload-dataset-files/FileUploader.module.scss to no longer contain the !important addition.
• improve state handling where it can be simplified in some way
• add real e2e test at least for this cases:
  • Upload a single file
  • Upload multiple files
  • Upload multiple files and cancel one.
  • And after each test navigate to the Dataset that the files were uploaded and check they exists in the Files Table
• display: contents causes an element's children to appear as if they were direct children of the element's parent, ignoring the element itself. This can be useful when a wrapper element should be ignored when using CSS grid or similar layout techniques. It's a bit fragile css hack and we should use a table here perhaps and not a Card to render the list of uploaded files.
• document differences with the JSF file upload
• implement dvwebloader using file upload page #468

What kind of user is the feature intended for?
(Example users roles: API User, Curator, Depositor, Guest, Superuser, Sysadmin)
Depositor

What inspired the request?
Uploading files feature.

What existing behavior do you want changed?

Any brand-new behavior do you want to add to Dataverse?
Uploading files feature.

Any open or closed issues related to this feature request?
#417

Start with the upload page and the remaining checklist items, especially FileJSDataverseRepository.ts, the DV-JS client, and the FileUploader.module.scss reference. Review the linked upload API documentation and issue #468 before choosing a remaining item. Done means the unchecked upload features are implemented and covered by the relevant upload-page tests.