scripts/generate-docs-index.mjs walks docs/**/*.md, parses YAML
front-matter (or first H1 fallback) and a Nygard-style ## Status
section, then writes docs/INDEX.md with grouped tables for ADRs,
Specs, Plans (with archive subsection), Patterns, and Other.
Pure Node 20 (no external deps); idempotent — running it twice
produces byte-identical output. Excludes adr/templates/, the ADR
README, INDEX.md itself, and any *_*.md sidecar file.
Wire-up:
- package.json: docs:index → node scripts/generate-docs-index.mjs
Initial run indexed 35 docs across the existing structure; the
generated INDEX.md is committed so the table is reviewable in the
PR before hooking generation into a pre-commit step.
