HasFileData should list not just files from a drag & drop, but also directory files, with paths or something

## Feature Request

Right now, if I drop a directory, I get evt.files() that just has the name of the directory. I would want to see the full list of all files in that directory and all subdirectories, equivalent to https://developer.mozilla.org/en-US/docs/Web/API/HTMLInputElement/webkitdirectory#understanding_the_results

More thoughts in discord thread: https://discord.com/channels/899851952891002890/1300590718766813344/1300593390873874463

## Implement Suggestion

I believe something here needs to be incorporated: https://developer.mozilla.org/en-US/docs/Web/API/DataTransferItem 's https://developer.mozilla.org/en-US/docs/Web/API/DataTransferItem/webkitGetAsEntry -- to not just read the files, but also the items as potential directories