feat: add Tooltip component and related hooks for improved UI interactions

- Implemented Tooltip component using Radix UI for better accessibility and customization.
- Created TooltipProvider, TooltipTrigger, and TooltipContent for modular usage.
- Added useIsMobile hook to detect mobile devices based on screen width.
- Updated themes with new color variables for better design consistency across the application.

components/ui/skeleton.tsx

@@ -0,0 +1,13 @@
+import { cn } from "@/lib/utils"
+
+function Skeleton({ className, ...props }: React.ComponentProps<"div">) {
+  return (
+    <div
+      data-slot="skeleton"
+      className={cn("bg-accent animate-pulse rounded-md", className)}
+      {...props}
+    />
+  )
+}
+
+export { Skeleton }