feat(#60): Clear basket on sign out

src/lib/components/SignOut.svelte

@@ -1,5 +1,7 @@
 <script lang="ts">
 	import { createEventDispatcher } from 'svelte';
+	import { basket, type Basket, type Item } from '$lib/stores/basket.js';
+
 	const dispatch = createEventDispatcher();
 
 	function emitSignedOutEvent() {
@@ -9,10 +11,23 @@
 	// Access the supabase client from the layout data
 	export let supabase: any;
 
+	let localBasket: Basket;
+	const unsubscribe = basket.subscribe((value) => {
+		localBasket = value;
+	});
+
 	async function signOut() {
 		// TODO use the error from the response
 		const { error } = await supabase.auth.signOut().then(() => {
 			emitSignedOutEvent();
+
+			// Clear the basket
+			localBasket = { items: [], subtotal: 0 };
+			basket.set(localBasket);
+			unsubscribe();
+			if (typeof localStorage !== 'undefined') {
+				localStorage.removeItem('basket');
+			}
 		});
 	}
 </script>