[24628] Several fixes in annotations

[richiware]

Description

This PR brings:

• Fixed generated code for @verbatim.
• Fixed @default when member type is an enumeration.
• Fixed @default_literal.
• Fixed registration of annotation which value is of string type.
• Removed old REST code.

Contributor Checklist

• Commit messages follow the project guidelines.
• Tests that thoroughly check the new feature have been added/Regression tests checking the bug and its fix have been added; the added tests pass locally
• Any new/modified methods have been properly documented.
• Changes are backport compatible: they do NOT break ABI nor change library core behavior.
• Changes are API compatible.
• Applicable backports have been included in the description.

Reviewer Checklist

• The PR has a milestone assigned.
• The title and description correctly express the PR's purpose.
• Check contributor checklist is correct.