refactor: Replace ShoppingCartIcon with ShoppingCart component in ProductCard and Market pages

- Update ProductCard.vue and Market.vue to use the new ShoppingCart component from lucide-vue-next instead of the previous ShoppingCartIcon from heroicons.
- Adjust button and icon imports for consistency across the application.

src/components/market/ProductCard.vue

@@ -16,7 +16,7 @@
           size="sm"
           class="absolute top-2 right-2 bg-blue-600 hover:bg-blue-700 text-white"
         >
-        <ShoppingCartIcon class="w-4 h-4" />
+          <ShoppingCart class="w-4 h-4" />
         </Button>
       
       <!-- Out of Stock Badge -->
@@ -104,7 +104,7 @@ import { ref } from 'vue'
 import { Card, CardContent, CardFooter, CardTitle } from '@/components/ui/card'
 import { Button } from '@/components/ui/button'
 import { Badge } from '@/components/ui/badge'
-import { ShoppingCartIcon } from '@heroicons/vue/24/outline'
+import { ShoppingCart } from 'lucide-vue-next'
 import type { Product } from '@/stores/market'
 
 interface Props {

src/pages/Market.vue

@@ -85,7 +85,7 @@
       <!-- Cart Summary -->
       <div v-if="marketStore.cartItemCount > 0" class="fixed bottom-4 right-4">
         <Button @click="viewCart" class="shadow-lg">
-          <ShoppingCartIcon class="w-5 h-5 mr-2" />
+          <ShoppingCart class="w-5 h-5 mr-2" />
           Cart ({{ marketStore.cartItemCount }})
         </Button>
       </div>
@@ -102,7 +102,7 @@ import { Button } from '@/components/ui/button'
 import { Input } from '@/components/ui/input'
 import { Badge } from '@/components/ui/badge'
 import { Avatar, AvatarImage, AvatarFallback } from '@/components/ui/avatar'
-import { ShoppingCartIcon } from '@heroicons/vue/24/outline'
+import { ShoppingCart } from 'lucide-vue-next'
 import ProductCard from '@/components/market/ProductCard.vue'
 
 const marketStore = useMarketStore()