More defensive guards on matchMedia and CSS.supports

[sunwrobert]

Hey, love the library. There's just a bit of an issue especially during vitest where I'm using jest-dom:

import "@testing-library/jest-dom"

I have to mock CSS.supports and window.matchMedia in the setup, but the problem gets worse because I'm using this library in a design-system, where a lot of other repos may be importing this. Can we alleviate some of the testing issues so we don't have to mock these two in every vitest setup?

Something like this would make consuming this library a lot more convenient #59