Feat(Core): Implement HL API

[stonebuzz]

Checklist before requesting a review

Please delete options that are not relevant.

• I have performed a self-review of my code.
• I have added tests (when available) that prove my fix is effective or that my feature works.
• I have updated the CHANGELOG with a short functional description of the fix or new feature.
• This change requires a documentation update.

Description

Replace #670

Screenshots (if appropriate):

[stonebuzz]

@SkiAn2007

Can you try this ?

Best regards

[stonebuzz]

@cconard96

I'd like your opinion on this.

Thank you in advance

[cconard96]

I don't have the plugin installed/configured anymore, but I didn't see anything in the code itself of concern as long as there is no way for the fields plugin to add fields to native custom assets and custom dropdowns. Both add custom fields to a "custom_fields" property and it doesn't seem like this code checks if it already exists to merge the properties instead.

Edit: Well maybe not... I haven't fully woken up yet. Are you trying to add the custom fields into the existing asset schemas or create new ones?

[stonebuzz]

Yes, now fields can add container fields to custom assets (not custom dropdown).

cf : #1112