Signals Notebook: Stoichiometry API endpoints may return incomplete columns until template drawing is refreshed

Description

When creating experiments from a template containing a chemicalDrawing entity, endpoints like GET /stoichiometry/{eid}/reactants endpoint sometimes returned only a subset of the configured columnDefinitions at first creation. After any manual update (e.g., hide/show columns), the endpoint returned the full list. 

Refreshing the chemical drawing entity within the experiment template resolves the behavior. 

This is usually caused by old chemical drawing entities in experiment templates after numerous updates to stoichiometry tables have been made.

Solution

- Open the experiment template that contains the chemicalDrawing entity.
- Remove the existing chemicalDrawing entity from the template.
- Add a new chemicalDrawing entity to the template in the same location and reconfigure it as needed.
- Save and republish the template so new experiments are created with the refreshed entity.
- Create a new experiment from the updated template and verify the behavior is resolved.
- If previously created experiments still show partial columns, toggle a column visibility (hide/show) once to force a refresh, or recreate the chemical drawing on the experiment.