fix: rotate normals with model to correct helicopter lighting during rotation

shaders/simple.vert

@@ -6,9 +6,10 @@ in layout(location=2) vec3 aNormal;
 out vec4 vColor;
 out vec3 vNormal;
 layout(location = 0) uniform mat4 transform;
+uniform mat3 normalMatrix;
 
 void main() {
     gl_Position = transform * vec4(position, 1.0f);
     vColor = aColor;
-    vNormal = aNormal;
+    vNormal = normalize(normalMatrix * aNormal);
 }