feat(nixos): add zeus desktop host

configs/nixos/hosts/zeus/default.nix

@@ -0,0 +1,41 @@
+{ pkgs, ... }:
+# zeus — Ryzen desktop with AMD graphics.
+# Disk layout is in ./disk.nix.
+# `fileSystems` are derived from it, none declared here.
+{
+  imports = [
+    ./hardware-configuration.nix
+    ./disk.nix
+  ];
+
+  system.stateVersion = "26.05";
+
+  # systemd-boot on the EFI system partition.
+  boot.loader.systemd-boot.enable = true;
+  boot.loader.efi.canTouchEfiVariables = true;
+
+  # Keep the desktop on a recent kernel for new AMD GPU support.
+  boot.kernelPackages = pkgs.linuxPackages_latest;
+
+  hardware.enableRedistributableFirmware = true;
+  hardware.graphics = {
+    enable = true;
+    enable32Bit = true;
+  };
+
+  # RAM-backed swap, no on-disk swap partition.
+  zramSwap.enable = true;
+
+  networking.networkmanager.enable = true;
+
+  hardware.bluetooth = {
+    enable = true;
+    powerOnBoot = true;
+  };
+
+  modules.desktop.enable = true;
+  modules.desktop.apps.steam.enable = true;
+
+  time.timeZone = "America/New_York";
+  i18n.defaultLocale = "en_GB.UTF-8";
+}