Add and maintain a status property to billable usage remittance DB records & messages (having possible values of `pending`, `failed`, `succeeded`).

Add a `billed_on` property (timestamp) to record the time of successful remittance.

Add an `error_code` property to record the failure reason if applicable. Error code should have possible values of `inactive`, `redundant`, `unknown` (we'll expand later as needed).

Add these fields to BillableUsageAggregate (to be used later).

Done:

• these fields are added to the database records with null values
• `GET /internal/remittance/accountRemittances`
  • Should only show different summary per status like successful , null state{} etc