feat(rust/signed-doc): catalyst-signed-doc-macro crate, catalyst_signed_documents_types_consts procedural macro

[Mr-Leshiy]

Description

Added a separate catalyst-signed-doc-macro crate, which will help to properly auto-generate some catalyst-signed-doc implementation based on the design specs. As an initial step added catalyst_signed_documents_types_consts macro, which generates catalyst signed documents types constants.

Related Issue(s)

Part of https://github.com/input-output-hk/catalyst-internal-docs/issues/266

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• My code follows the style guidelines of this project
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• I have made corresponding changes to the documentation
• My changes generate no new warnings
• 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
• Any dependent changes have been merged and published in downstream module