OpenAIResponse

OpenAI Chat Completion API response DTO.

This class represents the response structure from OpenAI's Chat Completion API. It supports both non-streaming and streaming (chunk) responses.

Example non-streaming response:

`{
"id": "chatcmpl-123",
"object": "chat.completion",
"created": 1677652280,
"model": "gpt-4o",
"choices": [{
"index": 0,
"message": {
"role": "assistant",
"content": "Hello!"
},
"finish_reason": "stop"
}],
"usage": {
"prompt_tokens": 10,
"completion_tokens": 20,
"total_tokens": 30
}
}
`

Example streaming chunk:

`{
"id": "chatcmpl-123",
"object": "chat.completion.chunk",
"created": 1677652280,
"model": "gpt-4o",
"choices": [{
"index": 0,
"delta": {
"content": "Hello"
},
"finish_reason": null
}]
}
`