Redact unauthorized data

Add a final step to the retrieval process to redact unauthorized results.

Look at how Elasticsearch does it for an example: https://gitlab.com/gitlab-org/gitlab/-/blob/master/app/services/search_service.rb#L62

This would require a user to be present so we would probably have a wrapper around ActiveContext.adapter.search(...) or pass user into it.

We would also need to define a condition for when a result should be visible to a user. Maybe every collection should define that.

Definition of done

• When performing a search, a user can only see results they should be able to