Allow non-integer divisors

[ssalbdivad]

This would allow types like:

const interval = type("number%0.1");

[TizzySaurus]

I looked into this after discussing with @ssalbdivad, and unfortunately we fall victim to floating-point errors. Things like type("number%0.1").assert("0.3") fail when they arguably shouldn't.

After bringing this up to @ssalbdivad on Discord they mentioned we should probably just not support decimal divisors since it's going to take more effort than is worthwhile to properly implement, and I think I agree.