feat(cart): refactor CartItem structure to remove nested product object and simplify access to properties

src/app/core/services/cart/cart.interface.ts

@@ -1,9 +1,3 @@
-export interface CartItemProduct {
-  nombre: string;
-  imagen: string | null;
-  variant: CartItemVariant | null;
-}
-
 export interface CartItemVariantOption {
   value: string;
   label: string;
@@ -27,7 +21,9 @@ export interface CartItem {
   precio_unitario: string;
   catalog_item_id: number;
   variant_id: number | null;
-  product: CartItemProduct | null;
+  nombre: string | null;
+  imagen: string | null;
+  variant: CartItemVariant | null;
 }
 
 export interface Cart {

src/app/core/services/cart/cart.service.spec.ts

@@ -24,15 +24,13 @@ describe('CartService', () => {
         precio_unitario: '10.00',
         catalog_item_id: 5,
         variant_id: 10,
-        product: {
-          nombre: 'Test Product (Size: M)',
-          imagen: null,
-          variant: {
-            id: 10,
-            precio: '10.00',
-            stock_tecnico: 1,
-            values: { size: 'M' },
-          },
+        nombre: 'Test Product (Size: M)',
+        imagen: null,
+        variant: {
+          id: 10,
+          precio: '10.00',
+          stock_tecnico: 1,
+          values: { size: 'M' },
         },
       },
     ],