chore: remove obsolete stdlib shim module

Author: pchalamet

src/FScript.Language/FScript.Language.fsproj

@@ -31,7 +31,6 @@
     <Compile Include="BuiltinTypes.fs" />
     <Compile Include="BuiltinSignatures.fs" />
     <Compile Include="BuiltinFunctions.fs" />
-    <Compile Include="Stdlib.fs" />
     <Compile Include="TypeInfer.fs" />
     <Compile Include="Eval.fs" />
     <Compile Include="Pretty.fs" />

src/FScript.Language/IncludeResolver.fs

@@ -420,7 +420,7 @@ module IncludeResolver =
                 program
                 |> List.choose (function | SImport(_, _, span) -> Some span | _ -> None)
                 |> List.head
-            raise (ParseException { Message = "Embedded stdlib source does not support 'import'"; Span = importSpan })
+            raise (ParseException { Message = "Embedded source does not support 'import'"; Span = importSpan })
         let prefix = tryGetSourceModulePrefix sourceName
         expandProgram dummyRoot fileSpan getOrCreatePrefix loadRef [] false sourceName prefix program