Add SIMD primitive comparison kernels

[connortsui20]

Summary

Moves the explicit AVX2 and AVX-512 primitive comparison kernels from #9547 into the handwritten comparison path. This leaves the RowFn work in #9547 and #9548 untouched while preserving the existing portable lane-kernel fallback on non-x86 targets and x86-64 CPUs without AVX2.

Changes

• Adds full-word SIMD kernels for all primitive types, comparison operators, and array/constant orientations, with scalar tail handling.
• Adds boundary and nullable coverage plus representative comparison benchmarks.
• Confirms the intended x86-64 codegen by cross-compiling for macOS: AVX2 uses packed ymm masks and AVX-512 uses zmm/k masks with direct bitmap stores. This environment cannot provide x86 runtime timings.

[codspeed-hq]

Merging this PR will improve performance by 11.66%

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⚠️ Different runtime environments detected

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⚡ 3 improved benchmarks
✅ 1978 untouched benchmarks
🆕 12 new benchmarks
⏩ 54 skipped benchmarks¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	WallTime	words_gather_scalar_avx2[65536]	9.4 µs	8.2 µs	+13.48%
⚡	Simulation	search_index_above_max_chunked	608.7 µs	549.4 µs	+10.78%
⚡	Simulation	search_index_in_range_chunked	610.1 µs	550.9 µs	+10.74%
🆕	WallTime	compare_f32_neon	N/A	5.4 µs	N/A
🆕	WallTime	compare_int_constant_left_neon	N/A	4 µs	N/A
🆕	WallTime	compare_u64_neon	N/A	4.6 µs	N/A
🆕	WallTime	compare_u8_neon	N/A	3.8 µs	N/A
🆕	WallTime	compare_f32_avx2	N/A	3.1 µs	N/A
🆕	WallTime	compare_int_constant_left_avx2	N/A	3.4 µs	N/A
🆕	WallTime	compare_u64_avx2	N/A	4 µs	N/A
🆕	WallTime	compare_u8_avx2	N/A	1.7 µs	N/A
🆕	WallTime	compare_f32_avx512	N/A	2.6 µs	N/A
🆕	WallTime	compare_int_constant_left_avx512	N/A	2.6 µs	N/A
🆕	WallTime	compare_u64_avx512	N/A	3 µs	N/A
🆕	WallTime	compare_u8_avx512	N/A	1.6 µs	N/A

Tip

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_{Comparing ct/primitive-comparison-simd (3e39406) with develop (e4b3421)}

Footnotes

1. 54 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩