Allow arbitrary formats for additional files

[vgskye]

Is your suggested enhancement related to a problem? Please describe.

For verifiability reasons, I'd like the ability to add cosign signature bundles as additional files to versions. Currently, labrinth only seems to accept "known" file types, even though additional files are just supplementary files that are not parsed anywhere as far as I'm aware.

Describe the solution you'd like

Only check for known file types on the primary file uploaded.

Describe alternatives you've considered

I could just zip up whatever binary blob into a zip and it'll be accepted, but that's... suboptimal for integration in automated procedures and the likes.

Additional context

No response

[Lgmrszd]

This will be very useful for uploading a save/world separate from the pack instead of bundling it in, to reduce the file size for those who don't need the world. Relatable for events like Modfest where the showcase world is optional.

[vgskye]

This will be very useful for uploading a save/world separate from the pack instead of bundling it in, to reduce the file size for those who don't need the world. Relatable for events like Modfest where the showcase world is optional.

for saves, they're already .zips, so couldn't you already upload them as an additional file as a zip is a recognized file format?