✨ feat: Remove Theme Switcher

- Update body class to use `dark` instead of `light` for dark mode
- Remove `ThemeSwitcher` component as it is no longer needed
- Update global CSS to set dark mode styles on the `.dark` class instead of `.light`

components/header/toolbar.tsx

@@ -2,8 +2,6 @@
 import Image from 'next/image';
 import Link from 'next/link';
 
-import { ThemeSwitcher } from './theme-switcher';
-
 import globePic from '../../public/globe.svg';
 import emailPic from '../../public/email.svg';
 import rssPic from '../../public/rss-feed.svg';
@@ -20,7 +18,6 @@ export default function Toolbar() {
             </div>
             <div className="flex items-baseline">
                 <ul className="inline-flex items-center gap-4">
-                    <ThemeSwitcher />
                     <li className="inline filter brightness-0 invert">
                         <Link href="#">
                             <Image