feat: restore some old perf things we tried

[Princesseuh]

Various experiments we did during dev but ended up dropping while we chased conformance, needs a lot of cleaning up, though.

[codspeed-hq]

Merging this PR will improve performance by 15.26%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 3 improved benchmarks
✅ 21 untouched benchmarks
🆕 7 new benchmarks
⏩ 8 skipped benchmarks¹

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	no plugins	2.1 ms	1.8 ms	+20.49%
⚡	noop HAST plugin (all elements)	3.4 ms	3 ms	+13.14%
⚡	no plugins	1.6 ms	1.4 ms	+12.31%
🆕	hast-text-noop (visit text nodes, no return)	N/A	3.1 ms	N/A
🆕	hast-elements-only (setProperty per element)	N/A	3.8 ms	N/A
🆕	hast-text-only (text replace per text node)	N/A	3.9 ms	N/A
🆕	mdast-text-only (text replace per text node)	N/A	2.9 ms	N/A
🆕	mdast-text-noop (visit text nodes, no return)	N/A	2.6 ms	N/A
🆕	mutating MDAST plugin (set depth on headings)	N/A	2 ms	N/A
🆕	parse_no_positions	N/A	750.6 µs	N/A

Tip

Curious why this is faster? Comment @codspeedbot explain why this is faster on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing feat/restore-perf (63da549) with main (b2ae465)²}

Footnotes

1. 8 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. ↩

2. No successful run was found on main (b9b2095) during the generation of this report, so b2ae465 was used instead as the comparison base. There might be some changes unrelated to this pull request in this report. ↩