Shaders: more graster-nodes no-std fixups (#3090)

* gcore-shaders: fix missing `num-traits/libm` features

* graster-nodes: fix missing cfg on use statements

* shaders: use unchecked Color constructors

* graster-nodes: remove async from shader nodes not needing it

* gcore-shaders: remove explicit fn pointer

* graster-nodes: make kurbo std-only

* graster-nodes: replace glam reexport with normal dep

* gcore: impl Display for ProtoNodeIdentifier

* unify glam workspace dep

node-graph/graster-nodes/src/lib.rs

@@ -1,8 +1,5 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 
-#[cfg(not(feature = "std"))]
-pub use graphene_core_shaders::glam;
-
 pub mod adjust;
 pub mod adjustments;
 pub mod blending_nodes;