🪖 Moves persistent store to svelte-utilities

app/src/lib/utilities/index.ts

@@ -1,3 +1,4 @@
 export * from './result'
 export * from './string-utilities'
+export * from './svelte-utilities'
 export * from './math-utilities'

app/src/lib/utilities/svelte-utilities.ts

@@ -0,0 +1,13 @@
+import { writable } from "svelte/store";
+
+export const persistentStore = (key:string, initialValue:any) => {
+    const savedValue = JSON.parse(localStorage.getItem(key) as string);
+    const data = savedValue !== null ? savedValue : initialValue;  
+    const store = writable(data);
+    
+    store.subscribe(value => {
+        localStorage.setItem(key, JSON.stringify(value));
+    });
+    
+    return store;
+}