neurolink: Skill for Claude Code

CI, generators and the advisory gate

Moved out of the root CLAUDE.md. The required-status-checks section is still in the root CLAUDE.md; stacked-PR and merge playbooks are in the neurolink-pr-merge skill.

⚠️ A "regenerate and diff" check needs a reproducible generator first

docs/api currency works because typedoc is a pure function of the source. docs-site/static/{llms.txt,llms-full.txt,search-index.json} were not, and a naive currency check over them would have been permanently red — the same shape of always-failing required check the ffmpeg incident below produced.

(Only search-index.json is committed now. The two llms files are gitignored: they are not in package.json files, so they never shipped, and committing a 9.5 MB whole-file regeneration conflicted on nearly every docs pull request. The reproducibility lesson below still stands — it is what lets the remaining artifact be diffed at all.)

Two separate causes, and the second is the one that hides:

1. build-llms-txt.ts stamped new Date().toISOString() into both llms files. Obvious once you look, and trivially fatal to any diff.
2. docFiles.sort((a, b) => a.order - b.order) is not a total order — many files share one order. Array.prototype.sort is stable, so ties fell back to the input order, which came from glob(), which is filesystem order. Two consecutive builds of an unchanged tree differed by 215,862 lines. sortSections had the same defect: every section outside SECTION_ORDER scores 999, so their ties came from Map insertion order.

Both are fixed in the llms generator, and those two artifacts are now byte-identical across runs.

search-index.json was not fixed with them, and this file said otherwise for months. The fix commit ef125b2bd touched five paths — the workflow, this file, build-llms-txt.ts, and the two llms artifacts. grep -c search-index over that file list returns 0. Its generator, docs-site/plugins/docusaurus-plugin-search-index/index.js, walked fs.readdirSync with no sort at all and numbered entries with a positional counter (objectID: String(id++)), so any reordering rewrote every later id and turned a one-file change into a whole-file diff; a rebuild on an unchanged tree differed by ~1,640 positions. That was the only one of the three artifacts still committed, and so the only one a currency check actually diffs.