API update

• Added simple and withReferenceField request examples to POST /tasks/{task_id}/structured-contents and POST /structured-contents. See the API reference for
• Documented that root_content is true for the top-level content and false for any content embedded through a reference field, consistent across the RecursiveStructuredContent, TaskStructuredContentCreateRequest, and LibraryStructuredContentCreateRequest schemas.
• Clarified the request shape for creating structured content that embeds other content through reference fields, on both POST /tasks/{task_id}/structured-contents and POST /structured-contents, with the following rules:
  • Field values must be nested under a fields object at every level (on the top-level content and on each embedded content_details) and has_embedded: true must be set on the top-level fields when creating new embedded items through a reference field.
  • Server-managed fields such as content_guid and created_by should not be sent. The server assigns them and returns each embedded item inline as expanded content_details. See the API reference for more details.

See the following API references for more details:

• POST /tasks/{task_id}/structured-contents – API reference.
• POST /structured-contents – API reference.