feat(core): add ScopedStylesMixin

[jorenbroekema]

What I did

1. Abstract the scoped styles functionality to a generic mixin, moving it from input-range to core package
2. Move tests pertaining to the scoped styles functionality in input-range to core as well
3. SkipLibCheck true until Fulfill deprecation notice to simplify type delivery open-wc/open-wc#2411 & testing-helpers: types import html und unsafeStatic from "lit-html/static", but should import from "lit/static-html". open-wc/open-wc#2388 are resolved

I have a use case where I could really use this scoped styles mixin:
I got a custom-element which relies on tailwind (global stylesheet) so I must use createRenderRoot -> this and make it render to LightDOM. However, there's custom styles that I'd still prefer to have scoped to prevent style conflicts/leakages.

[changeset-bot]

🦋 Changeset detected

Latest commit: a338271

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@lion/core	Patch
@lion/input-range	Patch

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[daKmoR]

I think that feature might be able to be implemented via an Lit controller...

care to try it out?

[gerjanvangeest]

You also need to update the input-range docs:

lion/docs/components/inputs/input-range/features.md

Line 95 in cc281b5

To use it when extending, override `static rangeStyles(scope)`:

[jorenbroekema]

Hm yeah I'll give it a shot

[jorenbroekema]

Looks like I succeeded :)

[jorenbroekema]

Ah crap I meant to squash and merge, 3 redundant commit messages now :P my bad