What problem does this feature solve?

We have the following error:

[rslint] Warning: JSON configuration is deprecated and will be removed in a future version.
[rslint] Please migrate to a JS/TS config. Run `rslint --init` to generate a new config file.

however when I run the command it has an error

error initializing config: config file already exists: rslint.json

What does the proposed API of configuration look like?

When a user already has a rslint.json and runs the init it would be helpful if we are prompted to reinitialize and migrate existing config.