/claim #12

Summary

• Add a distinct collaborative editor lock and checkpoint recovery ledger for the real-time research editor.
• Evaluate controlled section locks, stale-lock recovery, live presence, locked-section edit safety, autosave/local-cache health, hashed checkpoints, named restore points, and unresolved blocking comments/tasks.
• Produce restore plans, signed audit events, synthetic sample sessions, tests, requirement mapping, and short demo artifacts.

Demo

• collaborative-editor-lock-checkpoint-ledger/docs/demo.gif
• collaborative-editor-lock-checkpoint-ledger/docs/demo.svg
• npm run demo prints ready/review/blocked restore state plus signed audit evidence.

Verification

• npm run check
• npm test
• npm run demo
• npm run demo:gif
• git diff –check

Non-overlap

This is a lock/checkpoint recovery slice. It does not duplicate broad collaborative editor modules, operation replay engines, offline conflict rebasing, notebook workbenches, reference-formatting workbenches, or authorship/submission governance already submitted for issue #12.

AI-assisted with OpenAI Codex; I reviewed and verified the diff before submitting.