Improve HIPAA transmission security gates

[DENGXUELIN]

/claim #2054

Skill Improvement ($50-150 Bounty)

Related review issue: #2054

Summary

This improves hipaa-review by adding 45 CFR 164.312(e) transmission security evidence gates that require path-by-path ePHI transmission inventory, encryption, integrity, exception-route, recipient/BAA, and addressable-specification evidence before compliance is credited.

Changes

• Add HIPAA-TRANS-01 through HIPAA-TRANS-08 evidence gates.
• Require primary and exception ePHI transmission paths, including email, SFTP, EDI/AS2, vendor portal exports, webhook callbacks, support attachments, and emergency/manual transfers.
• Require per-path source, destination, ePHI elements, owner, external/BA recipient, encryption evidence, certificate/downgrade controls, integrity controls, and addressable rationale/equivalent controls.
• Extend output with path-level transmission evidence and gate results.
• Add skill-local benign and vulnerable JSON fixtures.

Bounty Tier

• Minor ($50) - Doc update, small logic tweak, typo fix
• Moderate ($100) - New edge case coverage, FP reduction with evidence
• Substantial ($150) - Rewritten detection logic, major coverage expansion

Validation

• git diff --cached --check
• git diff --check origin/main...HEAD
• JSON parse check for both fixtures
• Markdown fence balance check
• marker checks for HIPAA-TRANS-01 through HIPAA-TRANS-08
• added-line sensitive-pattern scan
• git merge-tree --write-tree origin/main HEAD matches HEAD^{tree}
• fork branch created through GitHub Git Data API; remote tree verified against local HEAD^{tree}

Payment preference

GitHub Sponsors, if accepted.