Reuse onboarding code for pre-join questions for public role selection

Onboarding looks like a pretty nice feature, there's something about Pre-join questions that makes me wonder... Why not dedicate a channel or something to a roles selection, similar to how Pre-joining has a selectable list of options which can ALREADY SET ROLES FOR A USER... It just makes sense! Make a channel dedicated to selecting roles! Colors, notifications, vanity, channel access based on interests, and more probably.

Take the already nice layout, already existing code, change it a bit to allow for just role selecting. I don't think it's a hard feature to implement and I bet a lot of people would like it! A lot of bots either use commands or are limited by how many buttons they can show below a message due to the limit which is fairly small imo.