[WIP] Add Slang shaders

[SaschaWillems]

⚠️Work in progress

Sample	Slang	Remarks
bloom	✅
bufferdeviceaddress	✅
computecloth	✅
computecullandlod	✅
computeheadless	✅
computenbody	✅
computeparticles	✅
computeraytracing	✅
computeshader	✅
conditionalrender	✅
conservativeraster	✅
debugprintf	✅
debugutils	✅
deferred	✅
deferredmultisampling	✅
deferredshadows	✅
descriptorbuffer	✅
descriptorindexing	✅
descriptorsets	✅
displacement	✅
distancefieldfonts	✅
dynamicrendering	✅
dynamicrenderingmultisampling	✅	Uses shaders from dynamicrendeering
dynamicstate	✅	Uses shaders from pipelines
dynamicuniformbuffer	✅
gears	✅
geometryshader	✅
gltfloading	✅
gltfscenerendering	✅
gltfskinning	✅
graphicspipelinelibrary	✅
hdr	✅
hostimagecopy	✅	Uses shaders from textures
imgui	✅
indirectdraw	✅
inlineuniformblocks	✅
inputattachments	✅
instancing	✅
meshshader	✅
multisampling	✅
multithreading	✅
multiview	✅
negativeviewportheight	✅
occlusionquery	✅
offscreen	✅
oit	✅
parallaxmapping	✅
particlesystem	✅
pbrbasic	✅
pbribl	✅
pbrtexture	✅
pipelines	✅
pipelinestatistics	✅
pushconstants	✅
pushdescriptors	✅
radialblur	✅
rayquery	✅
raytracingbasic	✅
raytracingcallable	✅
raytracinggltf	✅
raytracingintersection	✅
raytracingreflections	✅
raytracingpositionfetch	✅
raytracingsbtdata	✅
raytracingshadows	✅
raytracingtextures	✅
renderheadless	✅
screenshot	✅
shaderobjects	✅
shadowmapping	✅
shadowmappingcascade	✅
shadowmappingomni	✅
specializationconstants	✅
sphericalenvmapping	✅
ssao	✅
stencilbuffer	✅
subpasses	✅
terraintessellation	✅
tessellation	✅
textoverlay	✅
texture	✅
texture3d	✅
texturearray	✅
texturecubemap	✅
texturecubemaparray	✅
texturemipmapgen	✅
texturesparseresidency	✅
timelinesemaphore	✅	uses shaders from computenbody
triangle	✅
trianglevulkan13	✅
variablerateshading	✅
vertexattributes	✅
viewportarray	✅
vulkanscene	✅

[SaschaWillems]

When ready to merge: Add pre-compiled SPIR-V files.