Y24-418 - [BUG] Provide feedback mechanism from the Sequencescape job worker once Labware has been created

[StephenHulme]

Describe the bug

There is currently no feedback mechanism to SS/Limber once Assets/Labware have been created from the job worker.
This is causing race-conditions in Limber and Integration Suite not being aware of newly-created children, causing Integration Suite tests to fail (and probably some user confusion too).

Expected behaviour
The children list should accurately reflect what the children are (and display a user-friendly message while waiting for child-labware to be created).

Additional context
See:

• https://gitlab.internal.sanger.ac.uk/psd/integration-suite/-/jobs/1646901/artifacts/file/tmp/capybara/limber_rvi_bait_capture_library_prep_spec_38.png
• https://gitlab.internal.sanger.ac.uk/psd/integration-suite/-/jobs/1646901