feat: Mobile optimization and UI improvements

- Add mobile hamburger menu in TopBar with slide-in panel
- Optimize all components for mobile (responsive fonts, spacing, touch targets)
- Add proper viewport meta tags and safe area padding
- Fix /jackpot/next API to return active cycles regardless of scheduled time
- Remove BTC display from jackpot pot (show sats only)
- Add setup/ folder to .gitignore
- Improve mobile UX: 16px inputs (no iOS zoom), 44px touch targets
- Add active states for touch feedback on buttons

front_end/src/components/Footer.tsx

@@ -2,22 +2,22 @@ import Link from 'next/link';
 
 export function Footer() {
   return (
-    <footer className="bg-gray-900 border-t border-gray-800 py-8 mt-12">
+    <footer className="bg-gray-900 border-t border-gray-800 py-6 sm:py-8 mt-8 sm:mt-12 safe-bottom">
       <div className="container mx-auto px-4">
-        <div className="flex flex-col md:flex-row justify-between items-center">
-          <div className="text-gray-400 text-sm mb-4 md:mb-0">
+        <div className="flex flex-col md:flex-row justify-between items-center gap-4">
+          <div className="text-gray-400 text-xs sm:text-sm text-center md:text-left">
             © 2025 Lightning Lottery. Powered by Bitcoin Lightning Network.
           </div>
           <div className="flex space-x-6">
             <Link
               href="/about"
-              className="text-gray-400 hover:text-white transition-colors"
+              className="text-gray-400 hover:text-white transition-colors text-sm py-2"
             >
               About
             </Link>
             <Link
               href="/past-wins"
-              className="text-gray-400 hover:text-white transition-colors"
+              className="text-gray-400 hover:text-white transition-colors text-sm py-2"
             >
               Past Winners
             </Link>