albedo_rtx: cleanup

[DavidPeicho]

• [x] Shader included in binary as a compile-time feature, i.e.,

concat!(
            "..",
            path_separator!(),
            "shaders",
            path_separator!(),
            "spirv",
            path_separator!(),
            "blitting.vert.spv"
        ))

• [ ] Migrate pass to a simpler system
• [x] Compile shaders based on flags. Have a rust enum for flags:

enum IntersectorFlags {
    USE...
}

• [ ] Rename albedo_rtx to albedo_raytracing And then process source based on that?
• [x] Make helper function to create default passes
• [x] Do not rely on albedo_backend
  • [x] Take raw wgpu object in API
  • [x] Eventually panic! for wrong sized (bvh byte size, etc..))