feat: implement admin knowledge extraction system with document upload and AI pipeline integration

src/lib/storage.js

@@ -11,13 +11,13 @@ export const storage = {
    * @param {string} key - e.g. 'kb:topics'
    * @returns {any}
    */
-  get(key) {
+  get(key, defaultValue = null) {
     try {
       const item = window.localStorage.getItem(STORAGE_PREFIX + key);
-      return item ? JSON.parse(item) : null;
+      return item ? JSON.parse(item) : defaultValue;
     } catch (e) {
       console.error(`Error reading ${key} from storage:`, e);
-      return null;
+      return defaultValue;
     }
   },