feat(*): Add basket functionality

src/lib/stores/basket.ts

@@ -0,0 +1,41 @@
+import { writable } from 'svelte/store';
+
+const loadInitialState = () => {
+	// Check if localStorage is available (i.e., we're on the client side)
+	if (typeof localStorage !== 'undefined') {
+		const storedData = localStorage.getItem('basket');
+		return storedData ? JSON.parse(storedData) : getDefaultState();
+	} else {
+		return getDefaultState();
+	}
+};
+
+const getDefaultState = () => ({
+	items: [],
+	subtotal: 0
+});
+
+export const basket = writable(loadInitialState());
+
+// Subscribe to changes in the store and update localStorage accordingly
+if (typeof localStorage !== 'undefined') {
+	basket.subscribe((value) => {
+		localStorage.setItem('basket', JSON.stringify(value));
+	});
+}
+
+export type Basket = {
+	items: Item[];
+	subtotal: number;
+};
+
+export type Item = {
+	id: number;
+	categoryDescription: string;
+	name: string;
+	imgAlt: string;
+	imgSrc: string;
+	price: number;
+	priceId: string;
+	quantity: number;
+};