Integrate SIMDe to support cross-platform SIMD operations.

[YiJustin401]

Add unit test

[gaoj0017]

Thank you for the contribution. Could you please include some descriptions, or let us know if this is still a work in progress?

[YiJustin401]

Thank you for your feedback!
This PR integrates Simde to simulate AVX-512 instructions across different platforms, allowing RaBitQ to run tests even on systems without native AVX-512 support. Since I currently don’t have access to a machine with AVX-512, I’m not able to measure any potential performance impact—please feel free to test this on your side if possible.

I’ve also added a simple unit test script and a dataset generator, which can serve as a foundation for adding more unit tests in the future. This work is still in progress, and I’ll continue to improve the descriptions and related tests later.

Thanks again for reviewing and supporting this contribution!

[gaoj0017]

It is great if cross-platform SIMD could be supported by introducing SIMDe, but I have not yet explored whether it will bring consistent efficiency. Based on my personal experience, customized implementation is often necessary (I could be wrong though). We can keep the channel open and see whether SIMDe can make it.

[YiJustin401]

Thank you for sharing your thoughts. I’ll also provide some performance tests on AVX-512 in the future to see whether there is any efficiency drop when using SIMDe.