Feature Request: Return a structured error type instead of a bool on failed finalization #1939
Description
Describe the enhancement
finalize_psbt is where I noticed this pattern of returning a bool to represent if the finalization of a PSBT completed successfully. This is unhelpful to a developer since returning a bool does nothing except tell me what happened. There is nothing to tell me why. I can't react to specific forms of failure. I guess the expectation is that I would be able to check the transaction myself, but then the bool doesn't really do anything either then. Why wouldn't I just write something to check the transaction first and be confident that finalization occurred after that point?
My suggestion is to remove the bool return and instead update the signature to something like Result<(), SignerError> and update anywhere the process fails to instead fail earlier with a structured error that at least tells me where in the process the failure happened. This is a breaking change. Perhaps a middle ground to prevent a breaking change would instead be to keep the signature as is but just never return false. Instead, return errors where false would have been returned.
Use case
This would allow reacting to failures in the finalization process instead of just accepting the failure and crying myself to sleep at night.
Additional context
I don't mind working on this one since it is theoretically pretty straightforward.