The document is collected from `#[utoipa::path]` annotations through
`utoipa_axum::routes!`, which refuses a handler that has none, so an
unannotated route fails the build rather than silently leaving the
TypeScript client short an endpoint.
Health probes the three upstreams DESIGN.md §9.5 calls "Broken", always
answering 200 so a degraded service can still explain itself.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>