Refactor AdminPage and remove AdminPanel component: Simplify admin navigation by redirecting to preferences page and eliminating the AdminPanel component, streamlining the admin interface.

components/ui/Button.tsx

@@ -1,13 +1,17 @@
 "use client";
 
-import { ButtonHTMLAttributes, ReactNode, ElementType } from "react";
+import { ButtonHTMLAttributes, ReactNode, ElementType, AnchorHTMLAttributes } from "react";
+import Link from "next/link";
 
-interface ButtonProps extends ButtonHTMLAttributes<HTMLButtonElement> {
+type ButtonProps = ButtonHTMLAttributes<HTMLButtonElement> & {
   variant?: "primary" | "secondary" | "success" | "danger" | "ghost";
   size?: "sm" | "md" | "lg";
   children: ReactNode;
   as?: ElementType;
-}
+} & (
+  | { as?: Exclude<ElementType, typeof Link> }
+  | { as: typeof Link; href: string }
+);
 
 const variantClasses = {
   primary: "btn-primary border transition-colors",