Fix unintended Hub metadata calls from _patch_mistral_regex (#43603)
* Fix unintended Hub metadata calls from _patch_mistral_regex
* ruff fixes
* pass local files only
* Cache and fail-closed model_info call, add regression tests
- Wrap is_base_mistral with lru_cache so repeated loads of the same repo
id (notebooks, rollout loops, DDP workers) don't each hit the Hub.
- Swallow any Hub error in model_info — a 5xx/ratelimit/network hiccup
must not block tokenizer init for non-Mistral models.
- Add regression tests: (a) local_files_only=True never calls
model_info, (b) a Hub failure does not break _patch_mistral_regex.
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Co-authored-by: vasqu <antonprogamer@gmail.com>
Co-authored-by: Arthur <arthur.zucker@gmail.com>