Add Support For GPT 5.6 Family Open AI

[xRaTcHeT302]

Model: GPT 5.6
Creator: Open AI

https://developers.openai.com/api/docs/models/gpt-5.6-sol
https://developers.openai.com/api/docs/models/gpt-5.6-terra
https://developers.openai.com/api/docs/models/gpt-5.6-luna

[myk1yt]

Please modify it to support API Provider > OpenAI - ChatGPT Plus/Pro!