clouds: remove terrain-height march breaks causing holes

config.js

@@ -144,7 +144,7 @@ window.CONFIG = {
     // altitude so aircraft fly above the deck.
     clouds: {
         top: 1.0,                 // ~12.9 km
-        bottom: 0.0,              // deck base at the terrain datum
+        bottom: -0.2,             // ~-2.6 km (deck base slightly below terrain)
         // Coverage per weather level, 0 = clear, 1 = overcast. Only the
         // levels listed here override the built-in defaults
         // (sunny 0.20, cloudy 0.70, stormy 0.80, night 0.45). Live weather