Documents the snapshot tier and makes its use a convention. AGENTS.md gains the
test:snapshot / test:snapshot:record commands (and corrects the now-stale
`pnpm run test` include comment — the unit suite picks up examples/*/tests too),
plus a Conventions bullet: a change affecting the editor-facing transcript or
end-to-end agent UX needs a snapshot test (or an explicit note why none
applies); a pure internal refactor is exempt. The dsh-code-review skill gains a
matching reviewer-only check — review the golden diff itself, since a changed
*.golden is a behavior change in disguise.
Tianyi Cui
f09cc81c03