Health check — reports whether the data layer has symbols.

ok is about THIS PROCESS and never touches the database. data_fresh is a fact about the catalog that changes at most daily, and the uptime monitor asks every 15 minutes forever: reading it live meant the database could never be idle for five minutes, which is what Neon needs before it suspends a compute (2026-09-10, cost). It is now served from the data service's own short-lived catalog cache, so a probe costs nothing and the answer is at most that cache stale. The REAL freshness check — the one that pages — is the nightly data audit, unchanged.