Fix coco stream parsing

[djdameln]

Summary

This PR fixes an issue causing coco dataset parsing to fail in stream mode when the annotations json contains additional, unused keys. To achieve this, the PR adds a non-strict mode to the JsonPageMapper in the rust API, and uses it in the CocoPageMapper to allow and ignore unknown keys. With these changes, the behaviour of COCO parsing is now similar between stream mode and non-stream mode.

Changes:

• Adds strict argument to JsonPageMapper
• Enable strict mode for CocoPageMapper, while disabling it for other page mapper classes.
• Adds skip_serde_json_value function to rust/src/utils.rs
• Add unit test to confirm that unknown keys are ignored.

How to test

Checklist

• I have added unit tests to cover my changes.​
• I have added integration tests to cover my changes.​
• I have added the description of my changes into CHANGELOG.​
• I have updated the documentation accordingly

License

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  Feel free to contact the maintainers if that's a concern.
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# Copyright (C) 2025 Intel Corporation
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# SPDX-License-Identifier: MIT