`typeToCode` breaks when presented with records

<img width="812" height="252" alt="Image" src="https://github.com/user-attachments/assets/37449029-763c-4ecc-bb0c-dc8c61a3799b" /> This is happening where some of my models have records as member types. I would suggest creating a TypeVisitor in order to correctly represent all accepted types in code without erroring. At the very least json_serializable can give a useful error. `json_serializable: ^6.12.0`