[Feature Request] be consistent with nixos-rebuild

[luochen1990]

I attempted to build the same configuration using both colmena and nh/nixos-rebuild, then compared them. I discovered some subtle differences in the build outputs between the two, primarily in the suffix naming of drv files and the paths of the drv files themselves:

I wonder if it's possible to maintain as much consistency as possible between the two approaches, to avoid unnecessary duplicate builds and redundant boot options caused by repeatedly building with different tools.