Currently scim is overly abstract in representing attribute types.
Like using String for fields internally stored as iname.

@Firstyear suggested in #2994 (comment) to somehow add validation rules to attributes.

Not sure how those would look like, I think it'd be a bonus if they're usable for or translatable to the client side UI/UX.

https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input#attributes
interesting attributes: min, minlength, max, maxlength, pattern, type