Requested feature: Run on cargo packages nested in workspace root

Use case: Currently the extension won't run on a multi-root workspace (open workspace) structured like this:

workspace_root-1
├── cargo_package-1
│   └── cargo.toml
├── cargo_package-2
│   └── cargo.toml
└── cargo_package-3
    └── cargo.toml
workspace_root-2

Also won't work on a single-root workspace (open folder) structured like this:

(opened folder)
├── cargo_package-1
│   └── cargo.toml
├── cargo_package-2
│   └── cargo.toml
└── cargo_package-3
    └── cargo.toml

Link to relevant documentation (Rust reference, Nomicon, RFC): N/A

Test case:

N/A