Operation marker for accepting a previously stored proposed change. Acceptance means the document should apply the changes contained in proposal state and remove the proposal record once the processor has committed the change. This operation is part of the proposal/accept/reject workflow family. It separates review from mutation: Propose Change captures a request, Accept Change applies it, and Reject Change discards it. The corresponding Accept Change Workflow performs validation, policy checks, translation of sectionChanges, and final Update Document patching.