feat(layers): add FAA drone restrictions airspace layer

Show US prohibited and restricted special-use airspace from the keyless
FAA SUA FeatureServer as an off-by-default Infrastructure layer, with
share-link token 3 and an informational-only disclaimer.

src/data/layerState.js

@@ -595,6 +595,11 @@ export const LAYER_STATE_REGISTRY = Object.freeze([
     optionOwner: 'cctv',
   }),
   Object.freeze({ id: 'directions', token: 'n', disposition: 'enabled-only' }),
+  Object.freeze({
+    id: 'drone-airspace',
+    token: '3',
+    disposition: 'enabled-only',
+  }),
   Object.freeze({ id: 'earthquakes', token: 'e', disposition: 'enabled-only' }),
   Object.freeze({
     id: 'fire-perimeters',