Sort study search results

[dignissimus]

Resolves #12060

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The code looks alright, but this is blocked on testing with elastic search. I'm marking this as ready for review but this PR requires testing.

[kraktus]

Just saw that Lila-gitpod now support ES, that can be option to test your patch if you don't want to set it up locally: https://github.com/lichess-org/lila-gitpod/blob/657b5f9e91a8284b6bb6e8ad49b30d847014a4fe/docs/optional-services.md

[fitztrev]

Pulled this down to test it. I wasn't able to rebase so I ended up just reapplying the changes to a new branch. Here's my branch with @dignissimus's changes re-applied against the latest master.

Created a couple studies and I see the dropdown on the Study search result page.

At least in my environment, when a user hearts a study, the likes value isn't incrementing in elasticsearch. And some of the other orderBys don't seem to have an effect yet.

If anyone is going to test in gitpod, this will show you the data in elasticsearch:

docker compose exec lila bash -c "curl 'http://elasticsearch:9200/study/_search?pretty=true&q=*:*'"

[kraktus]

Maybe (probably in fact), need to change things in https://github.com/lichess-org/lila-search too