feat: implement onboarding flow with complex creation and email verification, and add Zustand for state management

apps/frontend/src/features/onboard/verify-email-page.tsx

@@ -0,0 +1,53 @@
+import { Button } from '@/components/ui/button';
+import { Route } from '@/routes/onboard/verify-email';
+import { Link } from '@tanstack/react-router';
+import { useEffect, useState } from 'react';
+
+export function VerifyEmailPage() {
+  const search = Route.useSearch();
+  const email = search.email || sessionStorage.getItem('pending-signup-email') || '';
+  const [resendCooldown, setResendCooldown] = useState(0);
+
+  useEffect(() => {
+    if (resendCooldown > 0) {
+      const timer = setTimeout(() => setResendCooldown((c) => c - 1), 1000);
+      return () => clearTimeout(timer);
+    }
+  }, [resendCooldown]);
+
+  const handleResend = async () => {
+    if (!email || resendCooldown > 0) return;
+
+    setResendCooldown(60);
+  };
+
+  return (
+    <main className="flex min-h-screen w-full items-center justify-center px-6">
+      <section className="w-full max-w-sm rounded-xl border bg-card p-6 text-card-foreground shadow-sm">
+        <h1 className="mb-2 text-2xl font-semibold">Verificá tu email</h1>
+        <p className="mb-4 text-sm text-muted-foreground">
+          Te enviamos un email de verificación a <strong>{email}</strong>. Hacé click en el link
+          para confirmar tu cuenta.
+        </p>
+
+        <div className="space-y-3">
+          <Button
+            type="button"
+            className="w-full"
+            onClick={handleResend}
+            disabled={resendCooldown > 0}
+          >
+            {resendCooldown > 0 ? `Reenviar en ${resendCooldown}s` : 'Reenviar email'}
+          </Button>
+
+          <p className="text-center text-sm text-muted-foreground">
+            ¿Ya verificaste tu email?{' '}
+            <Link to="/onboard/create-complex" className="text-primary hover:underline">
+              Continuar
+            </Link>
+          </p>
+        </div>
+      </section>
+    </main>
+  );
+}