test: add comprehensive test coverage

[fyvri]

📖 Overview

This pull request introduces additional test cases to improve the test coverage and reliability of the library. The changes focus on expanding the existing test suite to ensure robust validation of key functionalities, including marshaling/unmarshaling, NullUUID, Time and ClockSequence methods, and error handling in utility functions.

🛠️ Key Changes

1. Add marshal/unmarshal tests
   • Introduced new test cases to validate the correctness of marshaling and unmarshaling operations for UUIDs.
   • Ensures that UUIDs can be serialized and deserialized accurately across different formats.
2. Expand test coverage for NullUUID
   • Enhanced test coverage for the NullUUID type to verify its behavior in various scenarios, including null and non-null states.
   • Improves confidence in the handling of nullable UUIDs.
3. Add test for Time and ClockSequence methods
   • Added tests to validate the Time and ClockSequence methods, ensuring they produce accurate results based on the UUID's timestamp and clock sequence fields.
   • Confirms compliance with the UUID specification for time-based UUIDs.
4. Add test for randomBits panic on error
   • Included a test case to confirm that the randomBits utility function correctly panics when encountering an error during random number generation.
   • Strengthens error handling and ensures predictable behavior in edge cases.

🚀 Impact

• Improved Test Coverage: These changes significantly increase the test coverage of the library, reducing the risk of regressions and improving overall code quality.
• Enhanced Reliability: By validating critical functionalities and edge cases, the library becomes more reliable and robust for production use.
• Future Maintenance: Comprehensive tests make it easier for contributors to identify issues and extend the library with confidence.

Let me know if additional refinements are needed! 🙌