Usage calculations

[CathyBeil]

The "sent" amount in the "Overall message allowance" bar at the top should match the sum of the usage in the table below, right now it looks like it doesn't, but IDK if this is because we're using made up numbers or it's counting different things. I do know that when I look at counts in different places in prod it sometimes only shows delivered and other times shows all attempted including failed. I think we want to show everything including failed in both places.

[heyitsmebev]

You're right, @CathyBeil

"Usage" is counted differently depending on where you look in the app.

Currently, Service dashboard (/services/<id>) counts every notification we attempted to send (including all failures), and the Org dashboard "Overall Usage" chart also uses the same attempted count.

However, the Org dashboard per-service table and Org usage page (/organizations/<id>/usage) exclude failures and use billable counts instead.

We should use billable units for the Org Dashboard Usage count to keep things consistent. /organizations/id/usage and /services/id/usage) uses billable count.

[heyitsmebev]

@CathyBeil

Do we want to show free SMS message parts remaining or total message limit (annual quota)? To be consistent with the per-service table, free SMS message parts would make the most sense, but is that what we want to display here?