Adopt
Test management. Standalone (not tied to Jira), integrates with GitHub via API, and generates a traceability matrix directly — requirement to test case to execution result. Well-established in regulated environments; the third-party testing engagement can be given TestRail access to submit results without manual data entry.
Chosen over Xray (requires Jira, ruled out by DEC-003) and Zephyr (less established in regulated contexts). See DEC-005.