Add Auth Index page (#323)

front/src/pages/auth/Index.tsx

@@ -0,0 +1,26 @@
+import { useEffect } from 'react';
+import { useNavigate } from 'react-router-dom';
+
+import { useMockData } from '@/auth/hooks/useMockData';
+import { hasAccessToken } from '@/auth/services/AuthService';
+import { Modal } from '@/ui/components/modal/Modal';
+
+import { Companies } from '../companies/Companies';
+
+export function Index() {
+  const navigate = useNavigate();
+  useMockData();
+
+  useEffect(() => {
+    if (hasAccessToken()) {
+      navigate('/');
+    }
+  }, [navigate]);
+
+  return (
+    <>
+      <Companies />
+      <Modal>Welcome to Twenty</Modal>
+    </>
+  );
+}