Fix unhandled exception when attempting to sign message for custom derivation address

[BamaHodl]

Description

This PR fixes the unhandled exception when trying to sign a message from a custom derivation path. The intention in the original code was to show a NotYetImplementedView with a custom text message describing the unsupported feature, however it was implemented as a raise of the view instead of a redirect, as well as a bad initialization of the view (bad parameters).

This pull request is categorized as a:

• New feature
• Bug fix
• Code refactor
• Documentation
• Other

Checklist

• I’ve run pytest and made sure all unit tests pass before sumbitting the PR

If you modified or added functionality/workflow, did you add new unit tests?

• No, I’m a fool
• Yes
• N/A

I have tested this PR on the following platforms/os:

• Raspberry Pi OS Manual Build
• SeedSigner OS on a Pi0/Pi0W board
• Other seedsigner-emulator

[newtonick]

ACK and tested. Congrats @BamaHodl on your first SeedSigner merged PR! I appreciate the time put into the PR.

[BamaHodl]

ACK and tested. Congrats @BamaHodl on your first SeedSigner merged PR! I appreciate the time put into the PR.

Thank you! Very proud to have been able to contribute to this project.