Add badge to footer linking to danielrosehill.com

- Badge set to 480px width with responsive max-width
- Links to danielrosehill.com in new tab
- Added 20px top margin for spacing

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

index.html

@@ -15,6 +15,9 @@
         <footer class="footer">
             <p>💡 A late-night idea by <a href="https://danielrosehill.com" target="_blank">Daniel Rosehill</a></p>
             <p class="footer-date">October 31, 2025</p>
+            <a href="https://danielrosehill.com" target="_blank">
+                <img src="badge.png" alt="Daniel Rosehill" style="width: 480px; max-width: 100%; margin-top: 20px;">
+            </a>
         </footer>
     </div>