'Autofill' feature takes 1+ minute to render complex rig.json

[helen-m-lin]

Describe the bug When loading a complex rig.json to pre-fill the form, it may take upwards of 1min. This is noticed with complex jsons (in this case, it was a rig.json with 17 manufacturers).

To Reproduce Steps to reproduce the behavior:

1. Go to https://metadata-entry.allenneuraldynamics.org/
2. Click on the 'Autofill from file' button and select a rig.json file from local files.
3. See the loading indicator stating "Reading from file".
4. Observe that it may take 1+ min to see the new form with existing data.

Expected behavior We should profile this and see if we can make the render faster. Ideally it would take <10s even with complicated rig.json.

Screenshots

Desktop (please complete the following information):

• Browser: Edge, Chrome

Additional context

• This is related to adding the CustomTextWidget to render consts values. The effect may be unnecessarily calling the parent onChange callback.

[helen-m-lin]

Fix in #161 reduces time for the same rig.json to 5 seconds.