import { challengeMethods } from "https://deno.land/x/oauth2_server@0.12.0/resource_server.ts";
The default allowed PKCE code challenge methods. Clients SHOULD use PKCE code challenge methods that do not expose the PKCE verifier in the authorization request. Currently, "S256" is the only such method. https://datatracker.ietf.org/doc/html/draft-ietf-oauth-security-topics#section-2.1.1