I inspected the branch state and grouped the changes by logical purpose rather than by file count. Proposed commit structure feat(auth): add refresh token rotation Authentication service changes Token validation updates Related integration changes test(auth): cover refresh token rotation New authentication tests Expiration and invalid-token cases docs(auth): document token lifecycle Authentication flow documentation PR title Add refresh token rotation and coverage PR summary This PR introduces refresh-token rotation, adds coverage for expiration and invalid-token scenarios, and documents the updated token lifecycle. Review considerations Verify rotation behavior when an existing refresh token is reused. Confirm invalid and expired tokens are rejected as expected. No files were modified, staged, committed, or discarded. The structure above is based only on the changes inspected.