Adding migrations and lot of work. Starting work on the demo scope

docs/persistent-boards.md

@@ -1,6 +1,10 @@
 # Persistent boards, gated exhibits, and citation codes
 
-Status: **proposed** (design locked, not implemented). Extends the story flow graph
+Status: **demo subset implemented**. Migration 025 implements level-local boolean
+flags, normalized Document requirements, server-side filtering, persisted reveal
+acknowledgements, and the arrival animation. Board-key reuse, narrative-triggered
+live reveals, citation groups, and per-user playthrough overlays remain deferred.
+The broader design extends the story flow graph
 ([story-graph.md](story-graph.md)) and the narrative layer
 ([narrative-todo.md](narrative-todo.md)); interlocks with the Claim/Case Report
 work in [TODO.md](TODO.md) Milestone 5. Depends on the **flags / case-state**