ls: add some benchmarks

[sylvestre]

No description provided.

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/misc/stdbuf (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/misc/tee (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/timeout/timeout (passes in this run but fails in the 'main' branch)
Congrats! The gnu test tests/tail/overlay-headers is no longer failing!

[codspeed-hq]

CodSpeed Performance Report

Merging #8738 will not alter performance

_{Comparing sylvestre:perf-ls (955b100) with main (ea5c815)}

Summary

✅ 75 untouched
🆕 18 new
⏩ 1 skipped¹

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
🆕	ls_recursive_balanced_tree[(3, 4, 8)]	N/A	435.9 µs	N/A
🆕	ls_recursive_balanced_tree[(4, 3, 6)]	N/A	428.5 µs	N/A
🆕	ls_recursive_balanced_tree[(5, 2, 10)]	N/A	435 µs	N/A
🆕	ls_recursive_deep_tree[(100, 1)]	N/A	395.6 µs	N/A
🆕	ls_recursive_deep_tree[(20, 3)]	N/A	391 µs	N/A
🆕	ls_recursive_deep_tree[(50, 2)]	N/A	407 µs	N/A
🆕	ls_recursive_long_all_balanced_tree[(3, 4, 8)]	N/A	534.6 µs	N/A
🆕	ls_recursive_long_all_balanced_tree[(4, 3, 6)]	N/A	514.2 µs	N/A
🆕	ls_recursive_long_all_balanced_tree[(5, 2, 10)]	N/A	524.7 µs	N/A
🆕	ls_recursive_long_all_deep_tree[(20, 3)]	N/A	497.9 µs	N/A
🆕	ls_recursive_long_all_deep_tree[(50, 2)]	N/A	481.2 µs	N/A
🆕	ls_recursive_long_all_mixed_tree	N/A	1.9 ms	N/A
🆕	ls_recursive_long_all_wide_tree[(1000, 200)]	N/A	6.8 ms	N/A
🆕	ls_recursive_long_all_wide_tree[(5000, 500)]	N/A	32.5 ms	N/A
🆕	ls_recursive_mixed_tree	N/A	515.7 µs	N/A
🆕	ls_recursive_wide_tree[(1000, 200)]	N/A	5.3 ms	N/A
🆕	ls_recursive_wide_tree[(10000, 1000)]	N/A	48.4 ms	N/A
🆕	ls_recursive_wide_tree[(5000, 500)]	N/A	23.9 ms	N/A

Footnotes

1. 1 benchmark was skipped, so the baseline result was used instead. If it was deleted from the codebase, click here and archive it to remove it from the performance reports. ↩

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/misc/stdbuf (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/timeout/timeout (passes in this run but fails in the 'main' branch)

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/misc/tee (fails in this run but passes in the 'main' branch)
Skipping an intermittent issue tests/timeout/timeout (passes in this run but fails in the 'main' branch)