fix(drone-airspace): show stale FAA snapshots as stale and cap them at a day

The source dropped the proxy's stale flag and fetch time, so the layer row
read nominal and freshly updated through an outage, and the proxy served its
last snapshot indefinitely. Carry stale and fetchedAt through the source as
Fire Perimeters does, date a stale snapshot by its fetch, and stop serving a
snapshot more than 24 hours old.

docs/CURRENT-STATE.md

@@ -4100,7 +4100,8 @@ Fire Perimeters uses capped, timed server reads with stale-on-error caching and
 Prohibited & Restricted Airspace is off by default (share-link token `8`) and sits in
 Infrastructure. The proxy pages `TYPE_CODE IN ('P','R')` from the FAA SUA
 FeatureServer, caps the body, and reuses a one-hour snapshot, serving the last
-good payload as stale when a refresh fails. An answer with no valid zone, or
+good payload as stale for at most 24 hours when a refresh fails; the layer row
+then reads STALE, dated by that snapshot's fetch. An answer with no valid zone, or
 paging that ends while the service still flags more records, counts as a
 failed refresh. Client-supplied URLs are rejected.
 Polygons keep holes; pick ownership is deliberately unregistered so sibling