Pipeline Creation too complex

[Ipotrick]

The creation of graphics and compute pipelines has too many nested structs and options.
For example separate source files for each shader is unnessecary and should be removed.
The structs to init pipelines should be reduced by a lot.

[GabeRundlett]

You think that vertex and fragment shaders should be locked into the same file by daxa? (obviously you could put the code in a header, but obv that's extra effort)