[Task]: Consistent way of handling errors from wallet-rs

[laumair]

Task description

All the errors that we are receiving from wallet-rs are stringified and their interface is different than what firefly is expecting.

The errors should be parsed from wallet-rs and they should follow a consistent interface. Then firefly should make the necessary changes.

Requirements

TBD

Acceptance criteria

TBD

Creation checklist

• [ ] I have assigned this task to the correct people
• [ ] I have added the most appropriate labels
• [ ] I have linked the correct milestone and/or project