fix: fix all build blocking errors for bun run build

concord-client/src/App.tsx

@@ -1,4 +1,4 @@
-import React, { useEffect, useRef, useState } from "react";
+import React, { useEffect } from "react";
 import { BrowserRouter as Router, Routes, Route, Navigate } from "react-router";
 import { QueryClientProvider } from "@tanstack/react-query";
 import { ReactQueryDevtools } from "@tanstack/react-query-devtools";