perf: SIMD common prefix

[DaniPopes]

Re-use impl from #46.

[codspeed-hq]

Merging this PR will degrade performance by 22.59%

❌ 4 regressed benchmarks
✅ 102 untouched benchmarks
⏩ 111 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
❌	common_prefix_length/32	646 µs	744.6 µs	-13.24%
❌	common_prefix_length/64	646 µs	744.6 µs	-13.25%
❌	common_prefix_length/8	576.4 µs	744.6 µs	-22.59%
❌	common_prefix_length/16	576.4 µs	744.5 µs	-22.58%

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_{Comparing dani/perf-cpl (bd16e69) with main (61ab7c7)}

Footnotes

1. 111 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. ↩