System status
Sources
Every upstream feed, reporting its own health.
GET /api/v1/sources
Boardone row per upstream feed, unhealthy first · poll → last success → freshness
Every event and every layer traces to one of these feeds. For each you get the poll interval, the last successful fetch, how close it is to going STALE, the staleness thresholds and the last error verbatim. A feed that fails is shown as failed; missing data is never shown as a clear state.
Loading /api/v1/sources…
Display the attribution string wherever you render a
source's data, and link the upstream. Every row above carries one.