Cardano Updates

- Introduced a new CONTRIBUTING.md file outlining contribution guidelines, development environment setup, and testing procedures.
- Enhanced README.md with updated project overview, key features, quick start instructions, and detailed API usage examples.
- Improved documentation structure for better navigation and clarity, including links to relevant resources and support channels.

- Replaced Draft7Validator with Draft4Validator in the schema validation logic.
- Enhanced code readability by formatting with ruff.

- Replaced Draft7Validator with Draft4Validator in the schema validation logic.
- Enhanced code readability by formatting with ruff.

- Changed expected error code from 5040 to 5000 in multiple DRep delegation JSON test files to reflect updated error handling.
- Added new integration test cases for DRep vote delegation, covering scenarios with matching and mismatching types, as well as handling of CIP-129 prefixes.
- Revised existing test cases to ensure correct DRep id handling and error messages.
- Updated DRep delegation guide to clarify the requirement of the `type` field for both key_hash and script_hash formats.

- Changed expected error code from 5040 to 5000 in multiple DRep delegation JSON test files to reflect updated error handling.
- Added new integration test cases for DRep vote delegation, covering scenarios with matching and mismatching types, as well as handling of CIP-129 prefixes.
- Revised existing test cases to ensure correct DRep id handling and error messages.
- Updated DRep delegation guide to clarify the requirement of the `type` field for both key_hash and script_hash formats.