Report sent and delivered message count separately in api

[1yuv]

What feature do you want to improve?
Reporting of the message status on api

Describe the improvement you'd like
The messaging/outgoing/total section in /api/v2/monitoring currently combines both sent and delivered messages as a delivered and is reported accordingly. For example:

  "messaging": {
    "outgoing": {
      "total": {
        "due": 275827,
        "scheduled": 13856,
        "muted": 172372,
        "failed": 9064,
        "delivered": 192303
      },

Instead of this, report sent and delivered separately since they mean different things.

Describe alternatives you've considered
Instead of combining, report sent and delivered separately. This is already available in medic-admin/message_queue view. Updating this view would allow us to report sent and delivered separately. The expected output can be something like this:

  "messaging": {
    "outgoing": {
      "total": {
        "due": 275827,
        "scheduled": 13856,
        "muted": 172372,
        "failed": 9064,
        "sent": 100000,
        "delivered": 92303
      },

Additional context
We saw many messages remained in Sent state forever and saw that FCHVs never got those messages and they kept on sending new message to the system, resulting in duplicate activities. (More on this medic/config-moh-nepal#1212). If we report sent and delivered separately, it'll be easy to see this in grafana and be more actionable.

[binokaryg]

Relevant issue & conversation:

• Allow for monitoring and alerting of SMS failure rate #6572 (comment)