🐛 fix: resolve mobile logout issue on iPhone

Fixed logout button not working on iPhone in mobile menu by ensuring
the menu closes before the async signOut operation. The race condition
was causing the signOut to be interrupted when the menu closed.

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

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

Author: ervwalter

apps/web/src/components/Header.tsx

@@ -97,9 +97,9 @@ export function Header() {
             ) : (
               <button
                 className={`text-left px-3 py-2 text-white hover:bg-brand-300 rounded ${visibility}`}
-                onClick={() => {
-                  signOut();
+                onClick={async () => {
                   setMobileMenuOpen(false);
+                  await signOut();
                 }}
               >
                 Log Out