fix: reduce noice based bumpmap

shaders/simple.frag

@@ -12,7 +12,7 @@ void main() {
     vec3 ambient = ambientStrength * vColor.rgb;
     
     // terrain bump mapping with multi‐octave noise based on world position
-    float bumpStrength = 0.4;
+    float bumpStrength = 0.1;
     float n1 = fract(sin(dot(vPosition.xz, vec2(12.9898, 78.233))) * 43758.5453);
     float n2 = fract(sin(dot(vPosition.xz * 0.5, vec2(93.9898, 67.345))) * 24634.6345);
     float noiseVal = mix(n1, n2, 0.5);