Revamp XML-Conduit-Stylist API to avoid hard-dependency on Haskell Stylist.

Add utils for implementing :target-within, ensure unlayered styles take precedance.

Fix @layer to play nicely with the conditional at-rules.

If you're not using that, its still integrated into core.
Since the @layer rules are stripped by ConditionalStyles this shouldn't make a difference.

Integrate @layer support into core engine!

Parse @layer rules.

Tweak priority to be a list for the sake of cascadeLayers.

Remove Stylist-Traits APIs from Stylist Core, leaving backwards-compatible stubs.

Fix build failure against new enough versions of 'text'.

Allow callers to define psuedoclasses via callback.

Drop legacy FIXME regarding media query ratios.

Add support for `@document regexp()`..

Treat ratios as fractional numbers.

I'm having trouble consulting the spec, but judging by sample CSS this looks right.

Add support for range types to media query interpretor.

This allows browsers to be more vague when fetching @imports.

Add hook for callers to run their own tests against attributes.

Add new style tree traversals.

Expand :is/:where lowering.

Codestyle: remove unnecessary parens.

Move :root handling into interpretor.

Test counters() handling against longhand rather than shorthand.

Because that's where it'll be passed

Start testing counters implementations, fix syntactic shorthand lowering for counter[s]() functions.