Fix Keycloak auth: optional chaining for useAuth hook

src/components/App/index.jsx

@@ -24,11 +24,19 @@ function AppContent() {
   );
 }
 
+const onSigninCallback = () => {
+  // Remove OIDC params from URL after signin
+  window.history.replaceState({}, document.title, window.location.pathname);
+};
+
 function App() {
   // Only wrap with AuthProvider if Keycloak is enabled
   if (isKeycloakEnabled()) {
     return (
-      <AuthProvider {...keycloakConfig}>
+      <AuthProvider 
+        {...keycloakConfig}
+        onSigninCallback={onSigninCallback}
+      >
         <AppContent />
       </AuthProvider>
     );