Integrate Redux for state management, replace useState with Redux store

reducers/qrCodesReducer.ts

@@ -0,0 +1,30 @@
+import { createSlice, PayloadAction } from '@reduxjs/toolkit';
+import { QRCode } from '../types';
+
+const qrCodesSlice = createSlice({
+  name: 'qrCodes',
+  initialState: [] as QRCode[],
+  reducers: {
+    addQRCode(state, action: PayloadAction<QRCode>) {
+      state.push(action.payload);
+      console.log('Added QR code to state:', action.payload);
+    },
+    toggleBookmark(state, action: PayloadAction<number>) {
+      const index = state.length - 1 - action.payload;
+      if (state[index]) {
+        state[index].bookmarked = !state[index].bookmarked;
+        console.log('Toggled bookmark for QR code at index:', index);
+      }
+    },
+    deleteQRCode(state, action: PayloadAction<number | null>) {
+      const index = state.length - 1 - (action.payload as number);
+      if (state[index]) {
+        console.log('Deleting QR code at index:', index);
+        state.splice(index, 1);
+      }
+    },
+  },
+});
+
+export const { addQRCode, toggleBookmark, deleteQRCode } = qrCodesSlice.actions;
+export default qrCodesSlice.reducer;