[Lightheartdevs]

Cancelling a model download or existing-file verification now shows Download Cancelled and Retry. Previously, the host returned idle with lastTerminalStatus: cancelled, and the dashboard removed the progress banner without showing the result.

The progress hook consumes that terminal record only for the transfer it observed, using the canonical target and timestamp. Historical, dismissed, completed, unrelated and older results are not revived. Retry retains the catalog filename; split-artifact progress remains associated with its primary artifact. Backend lifecycle semantics are unchanged.

Validation of head 5a506586a10dd6307159a42e72660e94a89ea27e:

• 148 affected frontend tests, focused ESLint and the production build passed. Three wire-contract regressions and the page regression fail on unchanged main and pass with this fix. Hosted CI passed 69/69 checks.
• Actual Edge controls on the Windows/WSL laptop showed Verifying → Cancel → Cancelling → Download Cancelled → Retry → Verifying → completion, using the reviewed fix(models): acknowledge and cancel existing artifact verification #7405 host agent and this exact UI bundle. Retry came directly from the banner. Full SHA256 and file identity/metadata remained unchanged for the existing 5.68-GB 9B artifact.
• Real Run returned the laptop to active 9B at 64K. Both diagnostic overlays were removed and the original host agent/dashboard restored.
• Production artifacts match combined tree 1b395f70ebae8a39ae834459e43f17578092b325 on main b9b1de03; 31 combined hook tests passed.

This is focused laptop acceptance. Full current-main installs and journeys on all four required fleet machines remain pending. The host-agent verification repair is separate in #7405.