Change

[Sosthene00]

Handling change on the Receiver

[Sosthene00]

The last commit is a suggestion, the scan_transaction and scan_transaction_with_labels distinction didn't feel quite right now that we should always scan for change labels. I propose that we only keep scan_transactions_with_label, but rename it without the with_labels, and instead add a bool. If caller pass it false, we just totally skip all labels including change.
The rationale for this would be to allow wallet that have other change strategies that don't imply silent payment to just scan plain no label outputs. This should also slightly improve performance. Anyway it's up to the caller to decide, even if we of course strongly advise for using sp change and turn this flag on.
Alternative to that would be to not even add this bool and just say "ok we always scan for labels, and every wallet as at least a change label"

[cygnet3]

Some minor stuff, looking good!