Test/core crypto primitives

[The-FOOL-00]

Summary

This PR expands unit test coverage across gitlawb-core crypto primitives and DID utilities. It focuses on validating failure paths and invariants around certificate structure, content addressing, DID parsing/validation, and identity signing.

Certificates (cert)

• Adds validation tests for wrong cert type, invalid to hash, and empty signatures
• Verifies tampered signatures fail verify_all
• Confirms threshold behavior for non-maintainer signers and threshold=0

Content IDs (cid)

• Ensures from_sha256_bytes matches from_git_object_bytes
• Adds CID parsing success/failure tests
• Validates distinct inputs produce distinct CIDs
• Adds SHA-256 hex conversion error cases and known empty-hash constant

DIDs (did)

• Confirms did:web and did:gitlawb cannot resolve to verifying keys locally
• Adds parsing validation for missing DID prefix and unsupported methods
• Validates supported method set and predicate helpers
• Verifies method_id extraction

Identity (identity)

• Adds seed round-trip coverage
• Verifies sign_b64 outputs valid base64url signatures
• Ensures wrong-key verification fails
• Adds signed payload round-trip and failure cases
• Adds invalid PEM error-path test

Testing

• cargo test --workspace --exclude gl
• cargo test -p gitlawb-core --doc

Notes

• Full workspace cargo test failed only for the gl test binary due to Windows Application Control (os error 4551). All other tests passed.

[The-FOOL-00]

Hey @kevincodex1 , could you approve the workflow run so CI can execute?
It's blocked on fork workflow approval. All checks pass locally
(fmt, clippy, 317 tests). Thanks!

[kevincodex1]

yeah running now. will merge once its good bro

[The-FOOL-00]

Hey @kevincodex1 - I noticed the red X on the merged commit.
Is that related to my changes or something else on main?
Happy to help investigate if needed.

[The-FOOL-00]

Also,
could you use "Create a merge commit" instead of squash merge?
I'd like to preserve the individual commits. Thanks!

[kevincodex1]

hello @The-FOOL-00 thank you so much for your contribution, I like better squash merge so its cleaner. you are still the author attributed to it right?

[The-FOOL-00]

makes sense, thanks for merging!

[The-FOOL-00]

also any idea what caused the red X on the merged commit? was that related to my changes or something else on main?

[kevincodex1]

its fine bro, its our release process havent configured yet the binary release flow. we are using release-please