Icon on scratch list for when a scratch in the family has a better score than you

[ethteck]

mkst comment: It would be nice if you could see whether someone had improved (but not necessarily matched) one of your scratches at a quick glance.

Open questions:

• should this be a new endpoint (similar to family) that just returns the score / match status of the best scratch in the family?
• if not ^ how should we do it efficiently? potentially makes more sense to do this lookup server-side (backend) rather than on clientside (frontend)