feat: introduce consensus error codes

[shumkov]

Issue being fixed or feature implemented

To better recognize and handle DPP consensus errors we need to assign unique error codes.

What was done?

• Refactored and restructured error classes
• Assign error codes to consensus errors
• Remove duplicate checks (i.e. structure validation on state level)

How Has This Been Tested?

With unit tests

Breaking Changes

None

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated relevant unit/integration/functional/e2e tests
• I have made corresponding changes to the documentation

For repository code-owners and collaborators only

• I have assigned this pull request to a milestone

[shuplenkov]

👍