Edit history for titles and descriptions

Scope lives in the title and the description, so neither can be quietly widened: every edit to either one keeps the version it replaced.

1. Edit the title or description of an issue, a feature request, a change request or a client request. A connected agent doing the same thing over MCP goes through exactly the same path.
2. Before the new text is written, the previous title and description are snapshotted, together with who made the change and when.
3. Nothing is recorded when an edit leaves both fields the same, so status changes, reassignments and comments do not create noise in the history.

The history is kept per item, newest first, and it is retained for the life of the record. There is no revision screen in the app yet, so today the history is read through the API rather than from a page you can click to. What matters day to day is that the old wording still exists, whoever made the edit and whichever surface they used.

Comments have their own, lighter version of this. Editing a comment marks it, and the bubble carries a small Updated note next to the text so the reader knows the wording moved after it was first sent.