Flexible property name serialization from OpenAPI documents

[niels-nijens]

Introduce a feature that enables a property to have a different serialized name in the OpenAPI definition compared to its actual name in the object. This feature would allow for greater flexibility and clarity in API design, making it possible to maintain consistent naming conventions within the codebase while presenting a more user-friendly or standardized naming scheme in the API documentation. For example, an object property named userId in the code could be serialized as user_identifier in the JSON response, aligning with different naming conventions or preferences.