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-select/BaseMultiselect.vue

@@ -437,9 +437,9 @@ export default {
       required: false,
       default: () => ({
         container:
-          'p-0 relative mx-auto w-full flex items-center justify-end box-border cursor-pointer border border-gray-200 rounded-md bg-white text-sm leading-snug outline-none max-h-10',
+          'p-0 relative mx-auto w-full flex items-center justify-end box-border cursor-pointer border border-gray-200 rounded-md bg-white text-sm leading-snug outline-hidden max-h-10',
         containerDisabled:
-          'cursor-default bg-gray-200 bg-opacity-50 !text-gray-400',
+          'cursor-default bg-gray-200/50 !text-gray-400',
         containerOpen: '',
         containerOpenTop: '',
         containerActive: 'ring-1 ring-primary-400 border-primary-400',
@@ -451,17 +451,17 @@ export default {
         multipleLabel:
           'flex items-center h-full absolute left-0 top-0 pointer-events-none bg-transparent leading-snug pl-3.5',
         search:
-          'w-full absolute inset-0 outline-none appearance-none box-border border-0 text-sm font-sans bg-white rounded-md pl-3.5',
+          'w-full absolute inset-0 outline-hidden appearance-none box-border border-0 text-sm font-sans bg-white rounded-md pl-3.5',
         tags: 'grow shrink flex flex-wrap mt-1 pl-2',
         tag: 'bg-primary-500 text-white text-sm font-semibold py-0.5 pl-2 rounded mr-1 mb-1 flex items-center whitespace-nowrap',
         tagDisabled: 'pr-2 !bg-gray-400 text-white',
         tagRemove:
-          'flex items-center justify-center p-1 mx-0.5 rounded-sm hover:bg-black hover:bg-opacity-10 group',
+          'flex items-center justify-center p-1 mx-0.5 rounded-xs hover:bg-black/10 group',
         tagRemoveIcon:
           'bg-multiselect-remove text-white bg-center bg-no-repeat opacity-30 inline-block w-3 h-3 group-hover:opacity-60',
         tagsSearchWrapper: 'inline-block relative mx-1 mb-1 grow shrink h-full',
         tagsSearch:
-          'absolute inset-0 border-0 focus:outline-none !shadow-none !focus:shadow-none appearance-none p-0 text-sm font-sans box-border w-full',
+          'absolute inset-0 border-0 focus:outline-hidden !shadow-none !focus:shadow-none appearance-none p-0 text-sm font-sans box-border w-full',
         tagsSearchCopy: 'invisible whitespace-pre-wrap inline-block h-px',
         placeholder:
           'flex items-center h-full absolute left-0 top-0 pointer-events-none bg-transparent leading-snug pl-3.5 text-gray-400 text-sm',
@@ -491,7 +491,7 @@ export default {
         groupLabelDisabled: 'bg-gray-100 text-gray-300 cursor-not-allowed',
         groupLabelSelectedPointed: 'bg-primary-600 text-white opacity-90',
         groupLabelSelectedDisabled:
-          'text-primary-100 bg-primary-600 bg-opacity-50 cursor-not-allowed',
+          'text-primary-100 bg-primary-600/50 cursor-not-allowed',
         groupOptions: 'p-0 m-0',
         option:
           'flex items-center justify-start box-border text-left cursor-pointer text-sm leading-snug py-2 px-3',
@@ -500,11 +500,11 @@ export default {
         optionDisabled: 'text-gray-300 cursor-not-allowed',
         optionSelectedPointed: 'text-white bg-primary-500 opacity-90',
         optionSelectedDisabled:
-          'text-primary-100 bg-primary-500 bg-opacity-50 cursor-not-allowed',
+          'text-primary-100 bg-primary-500/50 cursor-not-allowed',
         noOptions: 'py-2 px-3 text-gray-600 bg-white',
         noResults: 'py-2 px-3 text-gray-600 bg-white',
         fakeInput:
-          'bg-transparent absolute left-0 right-0 -bottom-px w-full h-px border-0 p-0 appearance-none outline-none text-transparent',
+          'bg-transparent absolute left-0 right-0 -bottom-px w-full h-px border-0 p-0 appearance-none outline-hidden text-transparent',
         spacer: 'h-9 py-px box-content',
       }),
     },