Include current activity status for members in `/leaderboards/{name}` response

[Eldemarkki]

It would be useful if the GET /leaderboards/{name} response included the current activity status of each member of the leaderboard. The information is needed so that we can display the coding status on the leaderboard page in the frontend, similar to what we already do on the friends list page.

[lajp]

I'm not sure if the current activity (or lack thereof) is something that should be shared by simply being a member of a leaderboard. The leaderboards are meant for comparing it's members on how much they have coded without having to share any details about the activities.

That being said, it would be possible to include this data for users that are either 1) friends of the requester or 2) users who have a public profile (or both), however this would complicate the endpoint quite a bit.