Enhanced activity feed UI in contribution graph day view

Problem to solve

When using the "day view" on the user profile page's contribution graph (click on a day), we list the contributions of that day. Right now, we only display a simple chronological list of changes which is not very helpful and inconsistent with our other activity feeds.

Proposal

Let's implement the new activity feed UI for the day contributions as well.

Something more like this	...instead of this

Solution

tbd

What does success look like, and how can we measure that?