atmosphere: add altitude-thinning distance haze

config.js

@@ -316,8 +316,16 @@ window.CONFIG = {
         physicalSky: true,        // Rayleigh sky scattering instead of pure theme gradient
         rayleighGain: 8.0,        // exposure for the physical sky term
         distanceFog: false,       // legacy aerial perspective is off
+        haze: {
+            enabled: true,
+            heightKm: 60,
+            scaleHeightKm: 8.5,
+            density: 0.25,
+            grayTau: 1.2,
+            gain: 1.0
+        },
         model: {
-            enabled: false        // volumetric atmosphere/fog removed
+            enabled: false        // legacy full atmosphere model remains off
         },
         hazeResidual: 0.30,       // surface colour surviving at the full fog distance
         cloudBrightness: 1.0,     // cloud albedo (theme hue, brightness from the model)