Impl Default trait for JSONSchemaDefine

[Entercat]

In most cases, only a few properties of JSONSchemaDefine are used, and it seems cumbersome to explicitly declare other properties. I have also made modifications to the code in the examples.

Before :

Box::new(chat_completion::JSONSchemaDefine {
    schema_type: Some(chat_completion::JSONSchemaType::Array),
    description: Some("...".to_string()),
    enum_values: None,
    properties: None,
    required: None,
    items: Some(Box::new(chat_completion::JSONSchemaDefine {
        schema_type: Some(chat_completion::JSONSchemaType::Number),
        description: Some("...".to_string()),
        enum_values: None,
        properties: None,
        required: None,
        items: None,
    })),
})

After :

Box::new(chat_completion::JSONSchemaDefine {
    schema_type: Some(chat_completion::JSONSchemaType::Array),
    description: Some("...".to_string()),
    ..Default::default()
    items: Some(Box::new(chat_completion::JSONSchemaDefine {
        schema_type: Some(chat_completion::JSONSchemaType::Number),
        description: Some("...".to_string()),
        ..Default::default()
    })),
})

[dongri]

[dongri]

@hytracen Thank you!
4012534
impl Default instead of #[derive(Default)]