Allow auth on JSON:API Index

[alexanderjsluiter]

Package

next-drupal (NPM package)

Describe the feature request

First off, this library has been wonderful to use, thank you all.

As I understand it, the /jsonapi index is public by default. However, in our instance, we require authentication to browse the index. We add a few headers to all of our requests, along with an auth() callback to add a token. Can authentication be optional when retrieving a resource collection URL from the index? From what I can tell, the async getIndex(locale?: Locale): Promise<JsonApiResponse> on line 991 of client.ts would need to allow a withAuth boolean parameter. I am working around this for now in our development environment, but our production JSON:API index has extra route requirements on it in Drupal. I am pretty new to working in Javascript and NPM modules, but I'm happy to help where I can.