chore: migrate to Tailwind CSS v4.0 (#632)

* chore: migrate PostCSS configuration to v4

* chore: update dependencies in package.json and package-lock.json

- Bump versions for autoprefixer, postcss, postcss-cli, prettier, and tailwindcss.
- Remove unused dependencies to streamline the project.

* chore: add @tailwindcss/postcss and update package-lock.json

* fix: update import paths in CSS files for consistency

* fix: change prefix from `hx-` to `hx:`

* chore: migrate primary color theme variables to CSS

* fix: remove unnecessary text decoration property from anchor styles in typography CSS

* fix: update CSS styles for improved consistency and clarity across components

* chore: clean up package.json and package-lock.json, remove unused dependencies, and update CSS imports for better organization

* fix: bulk replace prefix `hx-` with `hx:`

* fix: update tailwind css prefix

* fix: styling consistent issues

- steps counter fix in v4
- removed tailwind.css
- update hr border colors
- fix button cursor in v4
- fix border colors in various places

* fix: update class prefixes for consistency in menu and sidebar components

* fix: refine CSS classes and transitions for navbar and sidebar components

- Updated hamburger menu styles for improved animation and structure.
- Adjusted sidebar transition duration for smoother effects.
- Standardized class prefixes for consistency across components.

* fix: update border color in hero badge component for improved styling consistency

* fix: update tab button cursor style for improved user interaction

* chore: recompile css

* fix: dark mode color not applied for before / after elements

* fix: docs navigation

* chore: recompile CSS

* chore: update Tailwind CSS and PostCSS dependencies to version 4.0.17, recompile CSS, and add safelist

* fix: typo in class name and add back decoration-from-font for typography a tags

* fix: update class syntax for Tailwind CSS compatibility in mermaid code block

layouts/shortcodes/hextra/hero-section.html

@@ -3,7 +3,7 @@
 {{- $size := cond (ge $heading 4) "xl" (cond (eq $heading 3) "2xl" "4xl") -}}
 
 <h{{ $heading }}
-  class="not-prose hx-text-{{ $size }} hx-font-bold hx-leading-none hx-tracking-tighter md:hx-text-3xl hx-py-2 hx-bg-clip-text hx-text-transparent hx-bg-gradient-to-r hx-from-gray-900 hx-to-gray-600 dark:hx-from-gray-100 dark:hx-to-gray-400"
+  class="not-prose hx:text-{{ $size }} hx:font-bold hx:leading-none hx:tracking-tighter hx:md:text-3xl hx:py-2 hx:bg-clip-text hx:text-transparent hx:bg-gradient-to-r hx:from-gray-900 hx:to-gray-600 hx:dark:from-gray-100 hx:dark:to-gray-400"
   {{ with $style }}style="{{ . | safeCSS }}"{{ end }}
 >
   {{ .Inner | markdownify }}