Add support for AES-GCM key wrap algorithms (A128GCMKW, A192GCMKW, A256GCMKW)

[vyperdon]

Summary

This PR adds support for three new key management algorithms: A128GCMKW, A192GCMKW, and A256GCMKW as defined in RFC 7518.

Changes

New Features:

• Added A128GCMKW, A192GCMKW, and A256GCMKW algorithm implementations
• Added Base class for algorithm implementations to enable header parameter configuration
• Added Validator, Header, and NameResolver classes to improve code organization
• Fixed missing attribute reader for cek in JWE::Alg::AesGcm module

Backward Compatibility:

• All existing public APIs remain functional
• Deprecated several public methods that were not tested and should be internal:
  • JWE.check_params, JWE.check_alg, JWE.check_enc, JWE.check_zip, JWE.check_key
  • JWE.param_to_class_name
  • JWE.apply_zip, JWE.generate_header, JWE.generate_serialization
• All deprecated methods include warning messages with migration guidance

Architecture Changes:

I had to introduce a Base class for algorithms because the new AES-GCM key wrap algorithms need to configure additional parameters in the JWE header (IV and authentication tag). This was not possible with the previous architecture.

I also found it strange that some methods were publicly available but had no tests. Since I wasn't sure if they were intended for external use, I marked them as deprecated instead of making them private. This preserves backward compatibility while discouraging their use.

---

Let me know if you'd like me to adjust the wording or add anything!

[pandwoter]

@anakinj Hey 👋, could you please look into this? We are motivated to get those new algorithms supported, please share your feedback, we are happy to adjust the implementation accordingly 🫡

[anakinj]

Hi @pandwoter I'll try to find time in the very near future to check this out.