feat(huggingface): support reasoning tokens

[njbrake]

Description

PR Type

🆕 New Feature ## Relevant issues

Checklist

• I have added unit tests that prove my fix/feature works
• New and existing tests pass locally
• Documentation was updated where necessary
• I have read and followed the contribution guidelines```

[njbrake]

Integration tests: https://github.com/mozilla-ai/any-llm/actions/runs/18596097174

[codecov]

Codecov Report

❌ Patch coverage is 79.16667% with 25 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
src/any_llm/providers/huggingface/utils.py	65.90%	7 Missing and 8 partials ⚠️
src/any_llm/providers/huggingface/huggingface.py	86.30%	6 Missing and 4 partials ⚠️

Files with missing lines	Coverage Δ
src/any_llm/constants.py	100.00% <100.00%> (ø)
src/any_llm/providers/openai/utils.py	55.26% <100.00%> (+1.20%)	⬆️
src/any_llm/providers/huggingface/huggingface.py	82.78% <86.30%> (+11.53%)	⬆️
src/any_llm/providers/huggingface/utils.py	71.76% <65.90%> (+31.33%)	⬆️

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• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[njbrake]

Note that the only change here is that now "think" is also a possible field name. It seemed reasonable to me to add it.