S13 History and versions

Purpose	See who changed what; preview, restore and name versions.
SRS	COL-1, COL-2, CMD-29
Layout	Right panel in History mode (opened from “≡” > “Show version history” or quick actions); width 264. Header 40: “History” title, “Save version…” button, close.
Contents	Groups by session (ud-section per session: avatar, actor, “Today 14:02 · 23 changes”). Rows 40: summary “Changed fill of Button”, time tiny. Named versions as rows with a tag icon, title strong, description small muted. Filter dropdown (All, Named versions, by actor).
Preview	Selecting a row shows the document at that point read-only: ud-banner “Viewing 14:02 · Claude” with “Restore this version” and “Back to current”. Tools disabled except Move, Hand.
Save version dialog	Modal 440: title field, description area, “Save”.
States	Loading; long history (virtual list); restoring (as a new change, toast with Undo).

Figma frame S13 (annotated)

Callouts:

1. History header: Save version…, close
2. Filter dropdown
3. Sessions by actor, change rows, named version
4. Viewing a past state: Restore this version / Back to current