fix(lab): ouvrir le bon diagramme sans F5 (?id alias ?canvas + tri canvases)

Co-authored-by: Cursor <cursoragent@cursor.com>

memento-note/app/actions/canvas-actions.ts

@@ -34,7 +34,8 @@ export async function getCanvases() {
 
   return prisma.canvas.findMany({
     where: { userId: session.user.id },
-    orderBy: { createdAt: 'asc' }
+    /** Most recently updated first — default canvas matches latest work (agent output, edits) */
+    orderBy: { updatedAt: 'desc' },
   })
 }