Retrieves the current status of a batchable job or operation, along with its child jobs if applicable.

Use this endpoint for operations that were split into batches, such as activations large enough
to exceed the configured batch size. Unlike the standard job status endpoint, the identifier here
is matched only against batchable jobs; a record identifier is not accepted as a fallback.

When the batchable job is found, its child jobs are looked up and returned under an 'Items'
property, so the progress of each individual batch can be inspected alongside the overall status.