feat: add smooth site-wide animations with framer-motion

- Add framer-motion and tailwindcss-animate for transitions
- Add page transitions via AnimatePresence in the site layout
- Convert nav dropdown and mobile menu to animated motion components
- Add entry animation to the radio player widget
- Add reveal/stagger animations to the home page views
- Add shared motion utilities and reusable animated components

src/components/public/radio-player.tsx

@@ -1,5 +1,6 @@
 "use client";
 
+import { motion } from "framer-motion";
 import { useCallback, useEffect, useRef, useState } from "react";
 
 /**
@@ -228,7 +229,10 @@ export default function RadioPlayer() {
 	const border = "color-mix(in srgb, var(--color-text-muted) 18%, transparent)";
 
 	return (
-		<section
+		<motion.section
+			initial={{ opacity: 0, y: 20, scale: 0.95 }}
+			animate={{ opacity: 1, y: 0, scale: 1 }}
+			transition={{ duration: 0.4, ease: [0.25, 0.1, 0.25, 1] }}
 			aria-label={`${config.name} player`}
 			style={{
 				position: "fixed",
@@ -392,6 +396,6 @@ export default function RadioPlayer() {
 			{/* Hidden stream element. preload="none" so nothing loads until the user
           hits play (and browsers block autoplay with sound regardless). */}
 			<audio ref={audioRef} preload="none" />
-		</section>
+		</motion.section>
 	);
 }