Invoice History: adding my own notes - e.g. called client to chase payment

This addition would help track some of those interventions that don’t actually occur through Harvest.

Where payments are overdue, and I’ve already sent a reminder, I’d like the ability to be able to record a manual intervention – for example:

A. The fact that I’ve called/emailed/left a message for a client in relation to an invoice.
B. The fact that the client has emailed/confirmed by the phone when they will make a payment.

I don’t think it requires further email integration, just the ability to writes notes that show up in the Invoice History on dates that I write them.

What do others think?