Add ed25519 public key bytes wrapper

[DaughterOfMars]

Description of change

This PR adds a public key bytes wrapper that does not require validation to exist.

Type of change

Choose a type of change, and delete any options that are not relevant.

• [ ] Bug fix (a non-breaking change which fixes an issue)
• [x] Enhancement (a non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Documentation Fix

How the change has been tested

Modified a few existing tests to use the new type.

Change checklist

Add an x to the boxes that are relevant to your changes, and delete any items that are not.

• [x] I have followed the contribution guidelines for this project
• [x] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes

[semenov-vladyslav]

What is the purpose of such wrapper? In which way the wrapper "does not require validation"?

In my opinion, it adds extra code duplication without clear benefits. Could you please provide a non-trivial use-case example demonstrating benefits of the wrapper?

[DaughterOfMars]

It does not require validation of bytes for the type to be constructed, unlike PublicKey. This allows us to unpack a public key without guaranteeing anything other than the length of the bytes. We need this in shimmer because currently invalid bytes are allowed syntactically (something we hope to change for 2.0).