Mostly security changes, add nouveau as a boot option, simplify settings and prepare for home-manager options

hosts/jupiter/default.nix

@@ -1,4 +1,4 @@
-{ jovian, ... }:
+{ ... }:
 {
   imports = [
     ./boot
@@ -7,13 +7,10 @@
     ./hardware
     ./wireguard
     ../../modules/system
-    jovian.nixosModules.default
   ];
 
   system.lanzaboote.enable = true;
   system.libvirtd.enable = true;
 
-  jovian.steamos.useSteamOSConfig = true;
-
   networking.hostName = "jupiter";
 }