Permanently delete a transport draft. Returns the draft as it was immediately before deletion. Use this to withdraw a draft your system no longer needs — for example when the originating request is cancelled in the upstream system that created it. Only the draft itself is removed: if it was already submitted (status: finalized), the order, shipments, and tours it produced are kept and must be removed through their own endpoints. Deleting a recurring master also cancels its schedule so no further occurrences are generated; already-generated tours are kept. To stop a series without losing the master, send end-recurring to POST /drafts/{transportDraftId}/actions instead. A 200 means the draft is gone and the body is the exact state that was removed; a draft that never existed or was already deleted answers 404, so a repeated call is safe.