implemented tanstack query

frontend/src/utils/api/users.ts

@@ -0,0 +1,21 @@
+import { API_BASE } from "../../config/api.config";
+import Cookies from "js-cookie";
+
+export const fetchUsers = async () => {
+  console.warn("fetchUsers is fetching!");
+
+  const response = await fetch(`${API_BASE}/default/users`);
+  const data = await response.json();
+
+  return data;
+};
+
+export const confirmUser = async (username: string) => {
+  console.warn("confirmUser is fetching!");
+  const response = await fetch(
+    `${API_BASE}/default/confirm-user?username=${username}`,
+  );
+  const data = await response.json();
+  Cookies.set("selectedUser", username);
+  return data;
+};