[Experimental] Mistral-format FP8 quantization

[mgoin]

https://huggingface.co/nm-testing/Mistral-Small-3.1-24B-Instruct-2503-FP8

vllm serve nm-testing/Mistral-Small-3.1-24B-Instruct-2503-FP8 --tokenizer_mode mistral --config_format mistral --load_format mistral --quantization fp8

lm_eval --model local-completions --model_args model=nm-testing/Mistral-Small-3.1-24B-Instruct-2503-FP8,tokenizer=mistralai/Mistral-Small-3.1-24B-Instruct-2503,base_url=http://0.0.0.0:8000/v1/completions,num_concurrent=500,tokenized_requests=False --tasks gsm8k --num_fewshot 5
local-completions (model=nm-testing/Mistral-Small-3.1-24B-Instruct-2503-FP8,tokenizer=mistralai/Mistral-Small-3.1-24B-Instruct-2503,base_url=http://0.0.0.0:8000/v1/completions,num_concurrent=500,tokenized_requests=False), gen_kwargs: (None), limit: None, num_fewshot: 5, batch_size: 1
|Tasks|Version|     Filter     |n-shot|  Metric   |   |Value |   |Stderr|
|-----|------:|----------------|-----:|-----------|---|-----:|---|-----:|
|gsm8k|      3|flexible-extract|     5|exact_match|↑  |0.8886|±  |0.0087|
|     |       |strict-match    |     5|exact_match|↑  |0.8848|±  |0.0088|

[github-actions]

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