feat(preset-mini)!: use getComponent for variant parameter

[chu121su12]

With getComponent helper, existing variant-x can more safely accept bracket value.

This PR update the api of variant-x to use getComponent, in addition using h.bracket to process the passed parameter.

Breaking changes:

• Direct values support are now removed and need to be updated to use bracket. Affected variants are:
  • all combinators-x variants
  • selector-x
  • scope-x
    • scope-x no longer defaulted to class; x now must be a qualifying selector
  • all tagged pseudo-x variants
    • group-x, peer-x, parent-x, previous-x
• media-x variant can still use direct value for theme lookup, but missing key in the theme will no longer generate custom property value
  • this in turn aligns media-x syntax with support-x syntax
• layer-x and uno-layer-x variants can still use direct value, in addition to bracket due to similarity with css @variant container/parent
• Values in bracket are handled using h.bracket so previous value of, ex.: variant-[uno_css], needs to be updated to variant-[uno\_css] to account for h.bracket processing
• Combinator version of tagged pseudo are removed in favor of the pseudo implementation
• For tagged pseudo, added pseudo/label experimental feature by tailwind. This may be changed down the line.

Edit: added scope-x update
Edit 2: update label syntax

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