ALP decoding plugin

[a10y]

Follow up to #7314 this time for ALP

[codspeed-hq]

Merging this PR will not alter performance

✅ 1122 untouched benchmarks
⏩ 1455 skipped benchmarks¹

---

_{Comparing aduffy/patched-alp (4994f14) with develop (ae906c7)}

Footnotes

1. 1455 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. ↩