Exercise sixteen independently authored COM and keyboard controls against durable offline split/join queues. Verify automatic and reviewed reconciliation, dependent edits and receipts across reopen, preserved conflicts after native identity or hierarchy changes, and exact text/style/graph predictions after a cold OneNote save.

Validation: 53 offline sync tests, 138 Python tests, focused native controls, workspace Clippy and formatting; all three owned clones removed.

Assisted-by: gpt-6-astra