Update GitHub Models & Hugging Face support to dynamically list (trending) models

[eamodio]

We should dynamically query GitHub Models & Hugging Face to provide the list of (conversational) models to use.

Note, both GH Models and Hugging Face are severely limited if you are on an account without paid support. For example, many of the latest models (o3-mini, o1, deepseek) on GH Models limit token input to 4000 tokens (rather than the real model limit).

[eamodio]

To verify:

Open the AI model picker and choose a couple of models from GitHub Models and Hugging Face

[sergeibbb]

@eamodio
Hi. The problem that I mentioned earlier is related to this issue.

It asks for HuggingFace API Key even if the model is not selected.

[eamodio]

@sergeibbb good catch, fixed in da3a3fa

[sergeibbb]

@eamodio

That is fixed. I confirm.