chore(dependencies): update Tailwind CSS and related packages for improved styling

- Added @tailwindcss/postcss as a new dependency.
- Updated tailwindcss to version 4.1.11 for enhanced features and performance.
- Upgraded prettier-plugin-tailwindcss to version 0.6.13 for better formatting support.
- Adjusted postcss.config.js to use the new Tailwind CSS plugin structure.
- Removed the obsolete tailwind.config.js file as it is no longer needed.

worklenz-frontend/src/components/enhanced-kanban/EnhancedKanbanCreateTaskCard.tsx

@@ -128,7 +128,7 @@ const EnhancedKanbanCreateTaskCard: React.FC<EnhancedKanbanCreateTaskCardProps>
         marginBottom: 8,
         marginTop: 8,
       }}
-      className={`outline-1 ${themeWiseColor('outline-[#edeae9]', 'outline-[#6a696a]', themeMode)} hover:outline`}
+      className={`outline-1 ${themeWiseColor('outline-[#edeae9]', 'outline-[#6a696a]', themeMode)} hover:outline-solid`}
     >
       <Input
         ref={inputRef}