...because apparently it's not allowed to have dependencies in the workspace manifest if it only defines other members and isn't a member itself or something 🤷♂️
For the server and "client" to be able to communicate with eachother, I'll be using DBus (https://www.freedesktop.org/wiki/Software/dbus/) and the dbus-crate (https://crates.io/crates/dbus/). Also, it will probably be better to split the server and client/daemon and control utility in two separate projects (using Cargo's workspaces (https://doc.rust-lang.org/cargo/reference/workspaces.html)).