Workflow: divide or duplicate work safely

Duplication creates an independent copy; division intentionally distributes selected work/quantities into resulting items. Read current state and ETag, preview division when offered, obtain user approval, then call duplicateOrder/duplicateProcessItem or divideOrder/divideProcessItem with idempotency.

Expected state: returned IDs are distinct, ordering/history is explicit, source/result totals satisfy the preview, and a replay creates no extra records.