Changes to Send Message Async

added the new optional request property messages/items/anyOf[subschema #1: MessageCreate]/content/anyOf[subschema #1]/items/oneOf[subschema #1: TextContent]/signature

added the new optional request property messages/items/anyOf[subschema #1: MessageCreate]/content/anyOf[subschema #1]/items/oneOf[subschema #3: ToolCallContent]/signature

added the new optional request property messages/items/anyOf[subschema #1: MessageCreate]/content/anyOf[subschema #1]/items/oneOf[subschema #7: OmittedReasoningContent]/signature

removed the optional property created_by_id from the response with the 200 status

removed the optional property job_type from the response with the 200 status

removed the optional property last_updated_by_id from the response with the 200 status

removed the optional property updated_at from the response with the 200 status

the response property agent_id became required for the status 200

removed the expired enum value from the status response property for the response status 200

removed the pending enum value from the status response property for the response status 200

response property agent_id list-of-types was narrowed by removing types null from media type application/json of response 200

added the optional property agent_id to the response with the 200 status

added the optional property background to the response with the 200 status