Upgrade: Tailwind v4 (#5246)

* temp: move tailwind calls out of the layer

* temp: ts tailwind config

* upgrade: Tailwind v4
This got a little out of hand.
Had to add a relative reference to the stylesheet in any component that uses @apply instead of the utility classes directly.

* upgrade: bg-opacity is now a modifier

* fix: Classic menu buttons assume a border

* Update test expectations [skip ci]

* fix: New preflight removal pattern

* fix: Skeletons don't have skin

* Update test expectations [skip ci]

* fix: Missing @reference

* [auto-fix] Apply ESLint and Prettier fixes

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src/views/DesktopUpdateView.vue

@@ -61,6 +61,8 @@ onUnmounted(() => electron.Validation.dispose())
 </script>
 
 <style scoped>
+@reference '../assets/css/style.css';
+
 .download-bg::before {
   @apply m-0 absolute text-muted;
   font-family: 'primeicons';