Add S/MIME (emailProtection EKU) end-to-end test coverage:
- ValidateCommonName() now accepts email addresses for S/MIME certs
- S/MIME test profile (prof-test-smime) in seed data
- Phase 11 test: issuance, EKU, KeyUsage, email SAN verification
- EST config enabled in test Docker Compose
- Portable KeyUsage parsing (awk, works on BSD/GNU)
- Full test environment documentation (docs/test-env.md)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
shankar0123