Seamlessly integrate `dream2nix`

[blaggacao]

... for the packaging layer

[blaggacao]

First attempt and learning: nix-community/dream2nix#433

[blaggacao]

Bump priority to accomodate @Lord-Valen use case in nixt

This is already scoped within the forst layer of the packaging pipeline.

We hope for dream2nix to become the ecosystem's best curated collection of UX-optimized builders.

If somebody reads this more actively involved in the dream2nix project, please help out with project outreach to link up design goals and ideas.