add a new simpler foldable component example

Author: lovasoa

examples/official-site/sqlpage/migrations/52_foldable.sql

@@ -12,6 +12,12 @@ INSERT INTO parameter(component, name, description, type, top_level, optional) S
     ('expanded', 'If set to TRUE, the foldable item starts in an expanded state. Defaults FALSE', 'BOOLEAN', FALSE, TRUE)
 ) x;
 
+INSERT INTO example(component, description, properties) VALUES
+    ('foldable', 'A single foldable paragraph of text', json('[
+        {"component":"foldable"},
+        {"title":"The foldable component", "description": "This is a simple foldable component. It can be used to show and hide content. It is a list of items, each with a title and a description. The description is displayed when the item is expanded."},
+    ]'));
+
 INSERT INTO example(component, description, properties) VALUES
     ('foldable', 'A SQLPage-themed foldable list with Markdown', json('[
         {"component":"foldable"},