feat: add detection template for cuda and avx.

[SanftMonster]

Just for review, please don't merge it.

[martindevans]

AVX/AVX2/AVX512 detection should already be handled by this

[martindevans]

I deliberately avoided using NativeLibrary.SetDllImportResolver when I originally set this up, since it overwrites global configuration that may already be in use by the application.

[martindevans]

The intention when I originally introduced this was that new dependencies could easily be added (in order of preference, most preferred first) something like this:

return TryLoad("magic/libllama.dll", IsMagicSupported())
       ?? TryLoad("unicorns/libllama.dll", IsUnicornsSupported())
       ?? TryLoad("rainbows/libllama.dll", IsRainbowsSupported())
       ?? etc...

i.e. any new platform can simply be chained in, so long as you can write a boolean method that prechecks if that particular thing is supported.

I deliberately avoided using NativeLibrary.SetDllImportResolver since in theory it could have already been set externally on this assembly, and that would cause an exception the second time. I guess it's not a huge risk really, it just feels like a poorly designed API really (feels like it should be chainable).