Clarify Cxx.jl. Update calling-c-and-fortran-code.md (#49379)

* Update calling-c-and-fortran-code.md Drop mentioning Cxx.jl

Author: PallHaraldsson

doc/src/manual/calling-c-and-fortran-code.md

@@ -1118,9 +1118,7 @@ For more details on how to pass callbacks to C libraries, see this [blog post](h
 
 ## C++
 
-For direct C++ interfacing, see the [Cxx](https://github.com/Keno/Cxx.jl) package. For tools to create C++
-bindings, see the [CxxWrap](https://github.com/JuliaInterop/CxxWrap.jl) package.
-
+For tools to create C++ bindings, see the [CxxWrap](https://github.com/JuliaInterop/CxxWrap.jl) package.
 
 
 [^1]: Non-library function calls in both C and Julia can be inlined and thus may have

doc/src/manual/embedding.md

@@ -6,7 +6,8 @@ calling Julia functions from C code. This can be used to integrate Julia code in
 C/C++ project, without the need to rewrite everything in C/C++. Julia has a C API to make
 this possible. As almost all programming languages have some way to call C functions, the
 Julia C API can also be used to build further language bridges (e.g. calling Julia from
-Python or C#).
+Python, Rust or C#). Even though Rust and C++ can use the C embedding API directly, both
+have packages helping with it, for C++ [Jluna](https://github.com/Clemapfel/jluna) is useful.
 
 ## High-Level Embedding