docs: refresh README benchmarks post SIMD speedups

[mrecachinas]

Re-run criterion and pytest-benchmark on current master and update both tables. Drop the 16384x64 rows from the raw Rust table since those workloads cross the Rayon threshold and criterion's measurement interacts poorly with the thread pool; point readers to the Python table for representative large-array numbers. Expand the Python table to cover start/mid/end match positions and additional sizes.

[github-actions]

📊 Benchmark Comparison Results

Status	Benchmark	Base	PR	Delta
❌	check_bytes_arrays_first_within_dist[16384 elems,s=64,mid]	0.0430ms	0.0672ms	56.3% slower
❌	check_bytes_arrays_first_within_dist[16384 elems,s=64,end]	0.0872ms	0.1340ms	53.6% slower
❌	check_bytes_arrays_best_within_dist[16384 elems,s=64,end]	0.0898ms	0.1334ms	48.5% slower
❌	check_bytes_arrays_best_within_dist[16384 elems,s=64,mid]	0.0908ms	0.1334ms	47.0% slower
❌	check_bytes_arrays_best_within_dist[16384 elems,s=64,at 0]	0.0909ms	0.1335ms	46.8% slower
❌	check_bytes_arrays_all_within_dist[16384 elems,s=64,mid]	0.0887ms	0.1283ms	44.7% slower
❌	check_bytes_arrays_all_within_dist[16384 elems,s=64,at 0]	0.0887ms	0.1283ms	44.6% slower
❌	check_bytes_arrays_all_within_dist[16384 elems,s=64,end]	0.0894ms	0.1287ms	44.0% slower

➖ 37 benchmarks within noise (click to expand)

Benchmark	Base	PR	Delta
check_bytes_arrays_all_within_dist[ 512 elems,s=16,at 0]	0.0040ms	0.0042ms	6.4% slower
check_bytes_arrays_all_within_dist[ 512 elems,s=16,end]	0.0040ms	0.0043ms	6.5% slower
check_bytes_arrays_all_within_dist[ 512 elems,s=16,mid]	0.0040ms	0.0043ms	6.2% slower
check_bytes_arrays_all_within_dist[ 1024 elems,s=32,at 0]	0.0084ms	0.0090ms	6.7% slower
check_bytes_arrays_all_within_dist[ 1024 elems,s=32,end]	0.0084ms	0.0090ms	6.6% slower
check_bytes_arrays_all_within_dist[ 1024 elems,s=32,mid]	0.0085ms	0.0090ms	6.5% slower
check_bytes_arrays_best_within_dist[ 512 elems,s=16,at 0]	0.0048ms	0.0054ms	12.1% slower
check_bytes_arrays_best_within_dist[ 512 elems,s=16,end]	0.0041ms	0.0043ms	4.8% slower
check_bytes_arrays_best_within_dist[ 512 elems,s=16,mid]	0.0045ms	0.0049ms	8.4% slower
check_bytes_arrays_best_within_dist[ 1024 elems,s=32,at 0]	0.0087ms	0.0092ms	6.1% slower
check_bytes_arrays_best_within_dist[ 1024 elems,s=32,end]	0.0089ms	0.0092ms	3.8% slower
check_bytes_arrays_best_within_dist[ 1024 elems,s=32,mid]	0.0087ms	0.0092ms	5.7% slower
check_bytes_arrays_first_within_dist[ 512 elems,s=16,at 0]	0.0002ms	0.0002ms	0.5% slower
check_bytes_arrays_first_within_dist[ 512 elems,s=16,end]	0.0038ms	0.0043ms	11.9% slower
check_bytes_arrays_first_within_dist[ 512 elems,s=16,mid]	0.0020ms	0.0022ms	11.3% slower
check_bytes_arrays_first_within_dist[ 1024 elems,s=32,at 0]	0.0002ms	0.0002ms	0.3% faster
check_bytes_arrays_first_within_dist[ 1024 elems,s=32,end]	0.0083ms	0.0092ms	11.2% slower
check_bytes_arrays_first_within_dist[ 1024 elems,s=32,mid]	0.0043ms	0.0048ms	10.9% slower
check_bytes_arrays_first_within_dist[16384 elems,s=64,at 0]	0.0002ms	0.0002ms	4.1% slower
check_bytes_within_dist[127 bytes,d=500]	0.0002ms	0.0002ms	1.2% slower
check_bytes_within_dist[16 bytes,d=0]	0.0002ms	0.0002ms	2.2% slower
check_bytes_within_dist[64 bytes,d=100]	0.0002ms	0.0002ms	1.5% faster
hex_within_dist	0.0001ms	0.0001ms	5.9% slower
hd_bytes[1000-diff]	0.0002ms	0.0002ms	16.7% slower
hd_bytes[1000-same]	0.0002ms	0.0002ms	15.7% slower
hd_bytes[1024-diff]	0.0002ms	0.0002ms	13.6% slower
hd_bytes[1024-same]	0.0002ms	0.0002ms	15.1% slower
hd_bytes[3-diff]	0.0002ms	0.0002ms	9.0% slower
hd_bytes[3-same]	0.0002ms	0.0002ms	12.8% slower
hd_bytes[64-diff]	0.0002ms	0.0002ms	7.5% slower
hd_string[1000-diff]	0.0002ms	0.0003ms	16.2% slower
hd_string[1000-same]	0.0002ms	0.0003ms	26.4% slower
hd_string[1024-diff]	0.0002ms	0.0003ms	7.8% slower
hd_string[1024-same]	0.0002ms	0.0002ms	11.7% slower
hd_string[3-diff]	0.0002ms	0.0003ms	4.0% slower
hd_string[3-same]	0.0001ms	0.0001ms	0.6% faster
hd_string[64-diff]	0.0002ms	0.0002ms	0.0% faster

Legend: ✅ Faster (>5%) · ⚠️ Slower (5-30%) · ❌ Regression (>30%) · 🆕 New · 🗑️ Removed

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⛔ This PR has severe performance regressions (>20% slower). Please investigate before merging.