Add category counts for search results

Would it be possible to add a list of categories and the number of snaps found for each category to search results?

The use-case is for the upcoming Flutter Ubuntu Software, discussion here [1].

I see this working in 1 of 2 ways:

1. If the "categories" field is included in the request parameters.
2. If a separate parameter is sent, such as "category_counts".

Either way an additional node at the top level of the search results could be added:
{
  ...
  "categories": [
    {
       "name": "education",
       "title": "Education",
       "results": 10
    }
  ]
}

Obviously this is all made up and the implementation details may require some different output.

[1] https://github.com/ubuntu/app-store/issues/557