julia

876b653f - [JuliaLowering] Make `ccall`, `cglobal` identifiers, not `K"core"` (#61372)

[JuliaLowering] Make `ccall`, `cglobal` identifiers, not `K"core"` (#61372) `cglobal` and `ccall` in flisp lowering are just identifiers that get special handling when called and special errors when they appear on the LHS of an assignment or function definition. JuliaLowering uses `K"core"` for them instead of `K"Identifier"`, but doesn't handle `K"core"` outside of the special cases mentioned above—internals like `Compiler` will `import Mod: cglobal`, which JL can't handle. This PR just makes `ccall`, `cglobal` magic identifiers instead of magic `K"core"` identifiers. I think ideally ccall would be its own special form and cglobal an identifier with no special handling in lowering, but that would be a syntax evolution change. Also include some other identifier validation cleanup