💾 store - added localstorage persistence

ref #1

app/src/App.svelte

@@ -14,6 +14,7 @@
                       href="https://docs.lauf-fuer-kaya.de/">See our configuration guide.</a></p>
               <form class="flex flex-col pt-3 md:pt-8" onsubmit="event.preventDefault();" on:submit={()=>
               {
+                  // TODO: validate token with backend api
                   console.log(token);
                   apikey.set(token)
               }}>

app/src/store.js

@@ -1,3 +1,7 @@
 import { writable } from 'svelte/store';
 
-export const apikey = writable('');
+const stored_apikey = localStorage.getItem('apikey');
+export const apikey = writable(stored_apikey);
+apikey.subscribe((value) => {
+	localStorage.setItem('apikey', value);
+});