It appears that OpenAI errors return a message field containing an ar…

…ray, instead of a string, for example:

{  "error": {
    "message": [
      "Invalid schema for function 'get_n_day_weather_forecast': In context=('properties', 'format'), array schema missing items"
    ],
    "type": "invalid_request_error",
    "param": null,
    "code": null
  }
}

This causes the JSON deserializer to choke.

There doesn't seem to be an official API documentation for error messages. However, since they appear to be only used for user feedback, I'd propose changing their type to be an unspecified `object`.

OpenAI.SDK/ObjectModels/ResponseModels/BaseResponse.cs

@@ -13,7 +13,7 @@ public record Error
 {
     [JsonPropertyName("code")] public string? Code { get; set; }
 
-    [JsonPropertyName("message")] public string? Message { get; set; }
+    [JsonPropertyName("message")] public object? Message { get; set; }
 
     [JsonPropertyName("param")] public string? Param { get; set; }