feat: drag and copy using alt+drag - #2738
No new findings
Incremental Code Review Summary
The latest PR head was reviewed against the current full diff. The implementation adds Alt-drag copying for overview frames and multi-frame selections, updates optimistic duplicate creation to use independent promises, preserves live preview content during structural copies, and adjusts primitive selection and keyboard shortcut handling. The targeted changes remain coherent: fresh refs avoid stale geometry, event prevention is deferred until the canvas will handle the shortcut, and the gesture tests cover cancellation, frame copying, and relative placement.
Risk assessment: Standard. No genuinely new actionable issues were found in this incremental pass. The previously reported multi-frame Alt-drag selection/camera issue at MultiScreenCanvas.tsx:5228 is still present and remains open; it was intentionally not reposted. The existing gesture suite was reported as passing (31 tests), and no other regressions were identified.
Key Findings
- No new findings in this incremental review.
- Existing open feedback remains unchanged and was not duplicated.
🧪 Browser testing: Will run after this review (PR touches UI code)