chore(flake): Stop restating the name each crate's Cargo.toml holds master
Every generated flake set `rust.pname`, and in 32 of 39 cases it restated the `[package].name` in the Cargo.toml beside it. nix-workspace now derives the name from that manifest, so the generator emits `pname` only for the seven virtual Cargo workspaces that have no [package] to take one from: fe-c, tangled-cli, tangled-spindle-nix-engine, nushell-plugin-tramp, oxidized-llvm, oxidized-pkg-config and oxidized-systemd. Nineteen crates said nothing else about their build, so their whole `rust` block goes with it. All 139 aarch64-linux and 41 aarch64-darwin drvPaths are unchanged, and each published flake still yields packages.<project-name>. Signed-off-by: Niclas Overby <niclas@overby.me>