add deck base config

hosts/nixos/deck/hardware-configuration.nix

@@ -0,0 +1,43 @@
+# Placeholder hardware configuration for Steam Deck
+#
+# This file must be generated on the actual Steam Deck hardware.
+#
+# To generate this file:
+# 1. Boot into the Jovian-NixOS installer ISO on the Steam Deck
+# 2. Run: nixos-generate-config --root /mnt --show-hardware-config > hardware-configuration.nix
+# 3. Copy the generated file to this location
+#
+# The generated file will include:
+# - CPU and GPU detection
+# - Storage device configuration
+# - Kernel modules for Steam Deck hardware
+# - File system configuration
+#
+# DO NOT attempt to use this placeholder for installation.
+
+{ config, lib, pkgs, modulesPath, ... }:
+
+{
+  imports = [ ];
+
+  # Placeholder - will be replaced by actual hardware detection
+  boot.initrd.availableKernelModules = [ ];
+  boot.initrd.kernelModules = [ ];
+  boot.kernelModules = [ ];
+  boot.extraModulePackages = [ ];
+
+  # Placeholder filesystem configuration
+  fileSystems."/" = {
+    device = "/dev/disk/by-label/nixos";
+    fsType = "ext4";
+  };
+
+  fileSystems."/boot" = {
+    device = "/dev/disk/by-label/boot";
+    fsType = "vfat";
+  };
+
+  swapDevices = [ ];
+
+  nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";
+}