feat!: change machine hostnames

Instead of merely naming my systems "laptop", "desktop", etc. (boring),
I now have them named after Aristotelian elements (cool).

This also gives me an excuse to refactor my flake file.

hardware-configuration/earth.nix

@@ -0,0 +1,23 @@
+{ config, lib, pkgs, modulesPath, ... }:
+{
+  boot.loader.grub.useOSProber = true;
+  boot.initrd.availableKernelModules = [ "xhci_pci" "ahci" "usb_storage" "usbhid" "sd_mod" ];
+  boot.initrd.kernelModules = [ ];
+  boot.kernelModules = [ "kvm-amd" ];
+  boot.extraModulePackages = [ ];
+
+  fileSystems."/" =
+    { device = "/dev/disk/by-uuid/c75eaa4d-9658-48e7-a2b3-1c6725ef8516";
+      fsType = "ext4";
+    };
+
+  fileSystems."/boot" =
+    { device = "/dev/disk/by-uuid/C7D1-82A6";
+      fsType = "vfat";
+    };
+
+  swapDevices = [ ];
+
+  hardware.enableRedistributableFirmware = lib.mkDefault true;
+  hardware.cpu.amd.updateMicrocode = lib.mkDefault config.hardware.enableRedistributableFirmware;
+}