Change GenerateImageAsync return objects => include revised_prompt

[LucGosso]

Feature Request

For Dalle3 they now return the revised_prompt,

would be nice if GenerateImageAsync returned same object => https://platform.openai.com/docs/api-reference/images/object

{
  "url": "...",
  "revised_prompt": "..."
}

instead of string array.

Thank you!

[StephenHodgson]

Sure, but is a breaking change

[LucGosso]

Make an overload of GenerateImageAsync ?

[StephenHodgson]

It's ok, I already have a plan for what to do. I also need to keep the unity package version of this in sync with proposed changes as well.