curvature: enable spherical Earth config

config.js

@@ -342,6 +342,15 @@ window.CONFIG = {
         brightness: 1.6           // overall glow of the catalogue points
     },
 
+    // ------------------------------------------------------------------
+    // Earth curvature
+    // ------------------------------------------------------------------
+    curvature: {
+        enabled: true,
+        earthRadiusKm: 6371,
+        exaggeration: 2.0
+    },
+
     // ------------------------------------------------------------------
     // Sun
     // ------------------------------------------------------------------