New rendersystemvulkan & vfx_vulkan
[hack] don't deal with instancing on SboxVertex for now, need some additional code around input layouts
[temp] don't mount any asset.party shaders
GetShaderFullPath: remove shader replacements and legacy prefix substitutes
Shader fixes where DXC is slightly less forgiving on bad syntax (has a bad hack for material api in it)
Rip up Material API to get it compiling
Initialize lightShades so we don't get undefined behaviour when summing them, should still be mostly stubbed out by the compiler anyway if shadingmodel doesn't use it
Latest compiled shaders