Expand description
A configuration node that resolves dependency paths from the Nix environment.
When running inside a nix-shell, all external dependencies (protoc,
openvmm-deps, kernel packages, UEFI firmware) are provided by Nix at
well-known paths exposed via environment variables. This node reads those
paths at runtime, writes them to a NixConfig struct, and issues the
corresponding cfg_versions::Request overrides so that downstream nodes
use the Nix-provided artifacts instead of downloading them.