UPDATE: Add LoadingScreen component to maintain consistency

frontend/src/components/Navigation/Sidebar.tsx

@@ -1,4 +1,4 @@
-import React, { useEffect, useRef, useState } from "react";
+import React, { useEffect, useState } from "react";
 import { Sidebar as SidebarIcon } from "lucide-react";
 import { useNavigate } from "react-router-dom";
 import { useAuth } from "../../context/AuthContext";