feat: add search operator and fields arguments

[dopry]

Add parameters for search_operator and search_fields when search is enabled on a query.

[dopry]

@zerolab what documentation are you looking for here? I added some inline the graphql type definitions so it shows up in graphiql.

[zerolab]

I was thinking developer docs (e.g. https://wagtail-grapple.readthedocs.io/en/latest/general-usage/model-types.html) so it is not buried in code

[dopry]

Are we creating documentation for consumers of of grapple or for grapple devs? We do not have any docs on the shared GraphQL Structures that this impacts and none of the enable_* options to the QuerySetList constructor or PaginatedQuerySet are exposed via the Decorators. I would propose the we create a new issue to document the structures... I feel like we need to document structures and how they are related to the decorators and GraphqlTypes... My understanding is that the structures are effectively base types for all of the generated GraphQL Types... so documenting those should probably go into GraphQL types. The new section of docs feels like a fairly large task on it's own... How do you feel about deferring this documentation effort to a separate task.... I found the current docs pretty intimidating as a new user and quite confusing... There is a lot of assumption that I would know what a field was and what the plural, singular, and paginated modified mean...

[zerolab]

We want docs for both consumers and devs. For example, as an implementer/user I would like to know that I can change the search operator

Now, my previous comment was me cheekily hoping to get that started here 🙈
Happy for a separate task. We do need to rehaul the documentation and add a few other things (https://github.com/torchbox/wagtail-grapple/issues?q=is%3Aissue+is%3Aopen+label%3Adocumentation) so happy for that to be handled as a follow up

[dopry]

Alright I'll work on tests next week. :)

[zerolab]

@dopry are you still keen to pursue this? We need some test, then I can do a full review/local testing pass and get it in

[dopry]

@zerolab I am, but I'm just getting back to work after summer break. It'll take me a few weeks at least to catch up on client work before I can take on any OSS work.

[dopry]

still on my radar, I'm wrapping up some work on django-oauth-toolkit that is a higher priority for me, so maybe a week or two out still.