Feat/crypto registry aes gcm siv

[Mehrn0ush]

As discussed in ticket #758, this PR adds AES-GCM-SIV as an AEAD variant to the Cryptography Registry.

Fixes #758

Details

• Adds standardized AES-GCM-SIV (RFC 8452) as an ae variant under the existing AES family

Scope

• Registry data only (schema/cryptography-defs.json)
• No schema or specification behavior changes

[bhess]

Thank you, @Mehrn0ush, for adding AES-GCM-SIV, this looks good to me.

Please check my comment regarding the pattern.
I also noticed some changes duplicated from your other PRs (XChaCha20, TUAK, and bcrypt). You might want to remove those from this PR to ensure a clean merge.

[Copilot]

Pull request overview

This PR adds AES-GCM-SIV support to the Cryptography Registry as requested in issue #758. However, it also includes several unrelated changes that were not mentioned in the PR description.

Changes:

• Adds AES-GCM-SIV (RFC 8452) as an AEAD variant to the AES family
• Adds XChaCha20-Poly1305 to ChaCha20 family variants (not mentioned in PR description)
• Removes BLAKE2b-HMAC variant (not mentioned in PR description)
• Fixes spelling errors in TUAK patterns (TUAC -> TUAK)
• Fixes typo in bcrypt pattern (closing parenthesis -> closing brace)

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[stevespringett]

Please update the pattern based on the suggestion from @bhess

[stevespringett]

Thanks for the PR. Could you resolve the issue that @bhess mentioned? Once corrected, we'll merge this in. Thanks again