Make it possible to change the $ref strategy of zod-to-json-schema

[FredrikNoren]

Confirm this is a feature request for the Node library and not the underlying OpenAI API.

• This is a feature request for the Node library

Describe the feature or improvement you're requesting

The "extract-to-root" strategy is not working for my types, but I tried changing the strategy to "none" which seems to work. It would be nice to be able to just pass down which strategy to use through zodFunction

Additional context

No response

[jovermier]

I have tested with the default extract-to-root and none with some surprising results. For a complex zod schema using extract-to-root schema uses 3 times as many input tokens than none. Your mileage may vary if using on simple schema. I have not observed any downsides when using none.