fix: gop cache LRU bug

[xupinjie]

Description

Set the maximum number of slots for the GOP cache.

Type of Change

Please select (at least one):

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation / examples / tutorials / demos
• Supporting functionality change (fix or feature in documentation generation, helper scripts, ...)
• Refactoring / internal change
• Other (please describe):

Testing

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• Tests added or updated if/as needed
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Documentation, Examples, Tutorials, Demos

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• User-facing documentation updated if/as needed (including API docs)
• Examples / tutorials / demos updated or added (if relevant)
• Limitations and constraints documented (if relevant)
• Performance documented (if relevant)
• Documentation building successful & checks outlined in the Documentation Checks section of the Contribution Guide are performed

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Code Quality

Checklist for dependencies:

• Dependencies updated in the relevant pyproject.toml if/as needed
• Code formatted according to the Code Formatting Guide

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Related Issues / Context

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References

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• docs/guides/DOCUMENTATION_SETUP_GUIDE.md
• docs/guides/FORMATTING_GUIDE.md

Please also refer to the summary checklist in the Contribution Guide,
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[RmSchaffert]

/build

[xupinjie]

/build

[RmSchaffert]

Thank you! Please see the in-line comment in the code and also add a sign-off to the commit.

[RmSchaffert]

This is not recognized as an enumeration of bullet points (and also leads to an error in the documentation generation due to the indentation in point 1). Please fix. You can e.g. add an indentation to make it an enumeration:

When useGOPCache=True:
    1. GOP replacement is per video: the cache keeps only one GOP per video
       (keyed by file path).
    2. Videos are evicted by LRU when the cache exceeds ``maxfiles`` entries.
    3. On a cache miss, the GOP is demuxed from the video file.