Upgrade to Vite 8 and Tailwind CSS 4 (#595)

- Vite 6 → 8 (Rolldown bundler), laravel-vite-plugin 1 → 3, @vitejs/plugin-vue 5 → 6
- Tailwind CSS 3 → 4 with CSS-based config (@theme, @plugin, @utility)
- Add @tailwindcss/vite plugin, remove postcss/autoprefixer/sass
- Convert SCSS files to plain CSS (resources/sass → resources/css)
- Migrate tailwind.config.js to CSS @theme directives
- Rename deprecated utility classes (shadow-sm→shadow-xs, outline-none→outline-hidden,
  rounded-sm→rounded-xs, bg-gradient-to→bg-linear-to, ring→ring-3)
- Migrate opacity utilities to color modifiers (bg-opacity, text-opacity,
  border-opacity, ring-opacity → color/N syntax)
- Update primary color CSS vars to full rgb() values for TW4 color-mix()
- Fix border-l color specificity for sidebar navigation (TW4 default border
  color changed from gray-200 to currentColor)
- Fix invalid border color classes (border-grey-light, border-modal-bg, border--200)
- Add @reference directive for @apply in Vue component style blocks
- Convert Vue component <style lang="scss"> blocks to plain CSS

resources/scripts/components/base/BaseRecurringInvoiceStatusBadge.vue

@@ -20,13 +20,13 @@ export default {
     const badgeColorClasses = computed(() => {
       switch (props.status) {
         case 'COMPLETED':
-          return 'bg-green-500 bg-opacity-25 px-2  py-1 text-sm  text-green-900 uppercase font-normal text-center'
+          return 'bg-green-500/25 px-2  py-1 text-sm  text-green-900 uppercase font-normal text-center'
         case 'ON_HOLD':
-          return 'bg-yellow-500 bg-opacity-25 px-2  py-1 text-sm  text-yellow-900 uppercase font-normal text-center'
+          return 'bg-yellow-500/25 px-2  py-1 text-sm  text-yellow-900 uppercase font-normal text-center'
         case 'ACTIVE':
-          return 'bg-blue-400 bg-opacity-25 px-2  py-1 text-sm  text-blue-900 uppercase font-normal text-center'
+          return 'bg-blue-400/25 px-2  py-1 text-sm  text-blue-900 uppercase font-normal text-center'
         default:
-          return 'bg-gray-500 bg-opacity-25 px-2 py-1 text-sm  text-gray-900 uppercase font-normal text-center'
+          return 'bg-gray-500/25 px-2 py-1 text-sm  text-gray-900 uppercase font-normal text-center'
       }
     })
     return { badgeColorClasses }