feat(layers): highlight aircraft broadcasting a transponder emergency

Flights and Military Flights tint aircraft red while the latest poll
carries squawk 7500/7600/7700 or an adsb.lol ADS-B emergency status
(general/unlawful/nordo/downed). Minimum-fuel and lifeguard priorities
are reported but not tinted. The Cockpit HUD aircraft-meta line names
the broadcast code in red. The status is not sticky: a cleared code
stops highlighting on the next refresh.

The analyst/voice query engine gains squawk, emergency and
emergencyKind fields. No new source or request: OpenSky state vectors
already carry the squawk and adsb.lol/readsb carries both fields.

Built by the Hex project (Crew Leo Agile dev team).

Co-Authored-By: Claude <[email protected]>

src/ui/styles/cyber.css

@@ -2270,6 +2270,12 @@
   color: rgba(205, 225, 226, 0.48);
 }
 
+:root[data-ui-theme='cyber']
+  body.cockpit-mode
+  .cockpit-aircraft-meta.emergency {
+  color: #ff4444;
+}
+
 :root[data-ui-theme='cyber'] body.cockpit-mode .cockpit-vision-controls {
   margin-top: 0;
   border-color: rgba(105, 203, 209, 0.38);