feat: make certificate page publicly accessible

- Add /certificate/* to public routes in root layout
- Display team leader name instead of current user
- Remove authentication requirement for viewing certificates
- Certificates now work without login

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

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

apps/hackathon/src/app/layout.tsx

@@ -52,6 +52,12 @@ export default function RootLayout() {
         return;
       }
 
+      // Certificate page - allow public access
+      if (pathname.startsWith('/certificate/')) {
+        setIsChecking(false);
+        return;
+      }
+
       // Require authentication for all other routes
       if (!session) {
         navigate('/auth/login', { replace: true });