Track number of crew executions

[whoabuddy]

We want to know this per crew, per user, and overall.

Edit: we also want to know number of chat executions and number of custom crew executions.

[r0zar]

Seems straightforward. Also seems like a good usecase for a sorted-set data structure.

With a sorted-set we can store the each of these executions with a compound-key, and assign a score (number of executions) so we can easily display it in a leaderboard like structure.

e.g. Get range CREW-USERX(100) => get top 100 user crews by execution count.