Marks the Drive-parity milestone: parallel transfers + background staging,
freeze/idle-GPU fixes, Drive recents, and full Google Drive feature parity
(persistence, publish history, COTS, SolidWorks REST). Git remains a dormant
fallback; its full removal is staged on chore/remove-git.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>