remove nodePackages.

(and save 5GB in the process)

- replace helvum with crosspipe.
- replace signal-desktop-bin with signal-desktop.

- remove `programs.adb.enable`; add android-tools to home packages.
- add file-roller and geary explicitly.

and disable unused.

using nixpkgs cache means all machines can use lix.

also update ghostty theme name.

doesn't work. don't know why.

and enable compute-runtime

use singular form if the config has lix.

- add rust utils: gpg-tui, ouch, systemctl-tui, mdns-scanner, rustscan, slumber, angryoxide, hwatch, trippy.
- remove xdg-ninja because I've given up on ever having a clean home dir.

- check if home module exists and include automatically; avoid specifying manually.
- use `mapAttrs` to apply `mkConfig` instead of specifying each time; also infer hostname from attrset name.
- use `listToAttrs <| map mkNode` to simplify list of nodes.

because mosh doesn't have scrollback.