Add SDSL member types to the manual and how they connect to GameStudio

[Doprez]

It would be nice to have a page dedicated in the manual to how specific shader variables can be used through code and GameStudio. There are a lot of questions in the discord usually about how Textures are supposed to be connected to a shader and the easiest way to currently figure that out is through looking at the source and existing shader implementations.

Types

TBD (Honestly I am pretty ignorant here so Ill come back to this and document when I have a bit more time.)