4640: Add `inRustProject` when-clause for commands in vscode r=vsrs a=vsrs
At the moment all rust-analyzer commands always visible in the command palette, even if there is no rust project opened.
This PR adds special [when-clause](https://code.visualstudio.com/docs/getstarted/keybindings#_when-clause-contexts) context. This context also might be used in key bindings.
Co-authored-by: vsrs <vit@conrlab.com>
Co-authored-by: vsrs <62505555+vsrs@users.noreply.github.com>
190a0595a4