Style: Enforce separation line between function definitions

I couldn't find a tool that enforces it, so I went the manual route:
```
find -name "thirdparty" -prune \
  -o -name "*.cpp" -o -name "*.h" -o -name "*.m" -o -name "*.mm" \
  -o -name "*.glsl" > files
perl -0777 -pi -e 's/\n}\n([^#])/\n}\n\n\1/g' $(cat files)
misc/scripts/fix_style.sh -c
```

This adds a newline after all `}` on the first column, unless they
are followed by `#` (typically `#endif`). This leads to having lots
of places with two lines between function/class definitions, but
clang-format then fixes it as we enforce max one line of separation.

This doesn't fix potential occurrences of function definitions which
are indented (e.g. for a helper class defined in a .cpp), but it's
better than nothing. Also can't be made to run easily on CI/hooks so
we'll have to be careful with new code.

Part of #33027.

servers/rendering/rasterizer_rd/shaders/sky.glsl

@@ -14,6 +14,7 @@ layout(push_constant, binding = 1, std430) uniform Params {
 	vec4 position_multiplier;
 	float time;
 }
+
 params;
 
 void main() {
@@ -40,6 +41,7 @@ layout(push_constant, binding = 1, std430) uniform Params {
 	vec4 position_multiplier;
 	float time; //TODO consider adding vec2 screen res, and float radiance size
 }
+
 params;
 
 #define SAMPLER_NEAREST_CLAMP 0
@@ -60,6 +62,7 @@ layout(set = 0, binding = 0) uniform sampler material_samplers[12];
 layout(set = 0, binding = 1, std430) restrict readonly buffer GlobalVariableData {
 	vec4 data[];
 }
+
 global_variables;
 
 #ifdef USE_MATERIAL_UNIFORMS
@@ -108,6 +111,7 @@ struct DirectionalLightData {
 layout(set = 3, binding = 0, std140) uniform DirectionalLights {
 	DirectionalLightData data[MAX_DIRECTIONAL_LIGHT_DATA_STRUCTS];
 }
+
 directional_lights;
 
 /* clang-format off */