adds middleware to sync redux with local storage also adds ununsed

import error rule to linter

frontend/src/store.ts

@@ -1,13 +1,31 @@
 import { configureStore } from '@reduxjs/toolkit';
 import { conversationSlice } from './conversation/conversationSlice';
-import { prefSlice } from './preferences/preferenceSlice';
+import {
+  prefListenerMiddleware,
+  prefSlice,
+} from './preferences/preferenceSlice';
+
+const key = localStorage.getItem('DocsGPTApiKey');
+const doc = localStorage.getItem('DocsGPTRecentDocs');
 
 const store = configureStore({
+  preloadedState: {
+    preference: {
+      apiKey: key ?? '',
+      selectedDocs: doc !== null ? JSON.parse(doc) : null,
+      sourceDocs: null,
+    },
+  },
   reducer: {
     preference: prefSlice.reducer,
     conversation: conversationSlice.reducer,
   },
+  middleware: (getDefaultMiddleware) => [
+    ...getDefaultMiddleware(),
+    prefListenerMiddleware.middleware,
+  ],
 });
 
+export type RootState = ReturnType<typeof store.getState>;
 export type AppDispatch = typeof store.dispatch;
 export default store;