import { ApolloClient, InMemoryCache, HttpLink, type NormalizedCacheObject } from "@apollo/client" let client: ApolloClient<NormalizedCacheObject> | null = null export function getClient() {  if (!client || typeof window === "undefined") {    const token = process.env.NEXT_PUBLIC_LITERAL_API_TOKEN     if (!token) {      console.warn("NEXT_PUBLIC_LITERAL_API_TOKEN is not set")    }     client = new ApolloClient({      link: new HttpLink({        uri: "https://literal.club/graphql/",        headers: {          authorization: token ? `Bearer ${token}` : "",        },      }),      cache: new InMemoryCache(),      ssrMode: typeof window === "undefined",      defaultOptions: {        query: {          fetchPolicy: "no-cache",          errorPolicy: "all",        },      },    })  }  return client}