Description on `fee reimbursement` transactions

[vindard]

Background

On ln payments without fee probes, we usually debit a "max fee" from the user, execute the payment, and then credit back the fee difference with the actual fee via a fee reimbursement transaction. This appears as 2 separate transactions in a user's transactions history.

Issue

The reimbursement transaction currently shows up as a credit from our Galoy wallet with no other context, which could be confusing for a user.

Should we flag these reimbursement transactions any differently somehow?

[pretyflaco]

Throwing out wording ideas, maybe sth like:

Description: Fee Reimbursement: Found cheaper route for payment {id}

Description: Fee Reimbursement: Found cheaper route previous LN payment

Description: Fee Back! Found cheaper route for previous LN payment

Description: Fee Back! Found cheaper route for payment {id}