validate-skills

# Instructions ## the pair a skill is one folder, named for its trigger, holding exactly two files: - `SKILL.md` carries the frontmatter and the numbered steps, and nothing above them - `<name>.sh` carries the sidecar, and the wayfinding header for the whole pair - the doc has no wayfinder of its own, since two headers that can disagree is worse than one - frontmatter opens line 1 with `name` matching the folder, and a `description` a reader sees - `metadata.kind` is declared rather than guessed, and decides the rest of the frontmatter - `kind: trigger` acts on the repo, so it sets `disable-model-invocation: true`; prose is not a gate - `kind: spec` describes a shape, so it stays auto-loading and never sets that flag - every frontmatter rule above is judged by `.claude/skills/export-readme/export-readme.sh` at the readme source; this pair's own checks stop at the body, the sidecar, the pairing, and the index ## the listing budget `description` and `when_to_use` are the whole listing; everything else loads only once a skill does: - the harness truncates the two of them, combined, at 1536 characters, and says nothing when it does - past the cap the tail is dropped, so a skill can lose the clause naming when it fires and still list - put the use case first, since a truncated listing keeps its opening and loses its end - `description` says what the skill does; `when_to_use` carries trigger phrases and example requests - the body is charged only when the skill loads, so long...