Move api client to a hook and allow .env api url config

web/app/util/auth.tsx

@@ -1,4 +1,4 @@
-import { client } from "./api";
+import { useApi } from "./api";
 import { useNavigate } from "@remix-run/react";
 import { createContext, useContext, useEffect, useState } from "react";
 
@@ -37,6 +37,8 @@ function useProvideAuth() {
 
   const navigate = useNavigate();
 
+  const client = useApi();
+
   const handleUser = (rawUser: string | null) => {
     if (rawUser) {
       setUser(rawUser);