Allow for Pydantic model field structured output without JSON schema validation

[ncoop57]

Howdy, really enjoy outlines, but ran into an issue when attempting to generate code using the current json structured output feature. Right now, I am wanting to generate data for a schema that looks like this:

class TinyProgram(BaseModel):
    requirements: str # A description of the requirements for the program to help the persona.
    code: str # The code that satisfies the requirements. Ensure it is well written and documented.

However, since the constrained output of the model is required to be valid json, the model fails to escape things like newlines or quotation marks reliably leading the model's output to be terrible for this task. Instructor lib has a nice way of handling this and I quite like their API and was wondering if it would be possible to have something similar with outlines so I don't need to use both for my project.