Postmortem edits no longer overwrite each other

A postmortem is often edited by a person and an agent at the same time. Saving one over the API or MCP now requires the version you edited. If someone changed it in the meantime, the save is refused and nothing is lost.

Dashboard editor. When the dashboard detects that the document changed underneath it, autosave pauses and a banner offers to reload.

API change. version is now required alongside the content when updating a postmortem. A stale version is answered with a conflict, so a client can fetch the latest and try again.