Build custom client for Mistral

Update: That client is most likely not supported anymore, so we should find another or build our own.

What about https://github.com/partITech/php-mistral ?
This seems quite good and has a recent release.

I checked it and techinically it has everything. Its more a strategic choice if a repo with 18 stars is good to add.

I would say that since it has Huggingface inference, something I had to build a custom client for, it is a good choice there also.

And we could always fork it in worst case scenario.