I see this error with the app, reported by NextJS, please fix it. The er

src/components/cost-estimator/cost-estimator-form.tsx

@@ -1,3 +1,4 @@
+
 "use client";
 
 import React, { useState, useTransition, useMemo } from 'react';
@@ -10,7 +11,8 @@ import { Step6Animations } from './step-6-animations';
 import { Step7Illustrations } from './step-7-illustrations';
 import { Step8Branding } from './step-8-branding';
 import { Step9AdditionalFeatures } from './step-9-additional-features';
-import { Step10Results, calculateTotalHours } from './step-10-results';
+import { Step10ShoppingCart } from './step-10-shopping-cart';
+import { Step11Results, calculateTotalHours } from './step-11-results';
 import { Card, CardContent } from '@/components/ui/card';
 import { AnimatePresence, motion } from 'framer-motion';
 
@@ -33,6 +35,7 @@ export type FormData = {
   illustrations: IllustrationSelection;
   branding: BrandingSelection;
   additionalFeatures: string[];
+  shoppingCart: boolean | null;
 };
 
 export function CostEstimatorForm() {
@@ -52,6 +55,7 @@ export function CostEstimatorForm() {
     },
     branding: null,
     additionalFeatures: [],
+    shoppingCart: null,
   });
   const [isPending, startTransition] = useTransition();
 
@@ -87,6 +91,7 @@ export function CostEstimatorForm() {
         },
         branding: null,
         additionalFeatures: [],
+        shoppingCart: null,
     });
     setCurrentStep(1);
   }
@@ -177,7 +182,16 @@ export function CostEstimatorForm() {
         );
       case 10:
         return (
-            <Step10Results
+          <Step10ShoppingCart
+            onNext={handleNextStep}
+            onBack={handlePrevStep}
+            onUpdateData={handleUpdateFormData}
+            formData={formData}
+          />
+        );
+      case 11:
+        return (
+            <Step11Results
                 formData={formData}
                 onReset={handleReset}
                 estimatedHours={estimatedHours}