Add Unlimited OCR

[guarin]

What does this PR do?

WIP branch to add Unlimited OCR: https://huggingface.co/baidu/Unlimited-OCR
Not ready for review

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• I confirm that this is not a pure code agent PR.

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• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

[github-actions]

CI Dashboard: View test results in Grafana

[github-actions]

[For maintainers] Suggested jobs to run (before merge)

run-slow: auto, unlimited_ocr