[RunConv][Add function] Unable to find column created during add function

Step to reproduce :

• Create a preparation
• Add a uppercase with a parameter `createNewField=true`
• Add another uppercase on the column created

To add a function, we need to get the column_name from the column_id picked from the preparation metadata.

The endpoint to add a function throws an error because the new column is not found in the payload prepV1 (API `GET /preparations/{id}/details/full`)

We need to analyze why this endpoint, which is supposed to bring back the preparation at the head step, brings only the root preparation.

So maybe we will need to check if we fix this api or if we can use the `/content` api or another to get these information.