Payload type for direct and proposed document-change operations. A Change Request describes what the caller wants to change, why it is being changed, and—when contract mutation is governed by section policy—how the change maps to logical document sections. `summary` is the human-readable explanation required when a proposal is stored for later acceptance. `changeset` is the list of patch entries for ordinary selected-document fields. `sectionChanges` is the structured form for modifying the document's `contracts` map through Document Section markers when Contracts Change Policy is enabled. This split exists so participants can review contract changes by section instead of accepting arbitrary low-level `/contracts` patches. A Change Request is data. It does not mutate by itself. Change Workflow, Propose Change Workflow, Accept Change Workflow, and Reject Change Workflow interpret it and produce processor patches or invalid-proposal events.