fix: usar dominio sandbox de Resend para emails

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/api/cliente/registro/route.ts

@@ -18,7 +18,7 @@ export async function POST(req: NextRequest) {
   });
 
   await resend.emails.send({
-    from: "Taller <noreply@taller.com>",
+    from: "Taller <onboarding@resend.dev>",
     to: cliente.email,
     subject: "¡Bienvenido al taller!",
     html: `