Describe the solution you'd like

json schema can let editor which support LSP to complete some configuration file. Such as:

There are many tools have supported json schema: https://json.schemastore.org/pyproject.json

Can tool.black be supported?

Describe alternatives you've considered

Refer cmhughes/latexindent.pl#206:

The steps are following:

1. Create a json schema
2. Add its URL to schemastore.