Rust toolchain is missing in container image

[lurtz]

The container image contains rust-analyzer and clangd / LLVM. But it misses e.g. rustc and rustfmt. Until now these have to be installed manually, see e.g. https://github.com/eclipse-score/inc_mw_per/blob/main/.devcontainer/devcontainer.json

Should these tools be added to the image instead?

[lurtz]

I especially need rustfmt, because I setup VS Code to automatically format code when saving. rust-analyzer throws in error in this case when rustfmt is missing in the image.

Maybe there is also a way to tell rust-analyzer to chose rustfmt from the toolchain