Hosts, Use directory-driven hosts in flake.nix

This adds some code to flake.nix to read the directory of hosts/ and
find all hosts based on their host.nix file, and set the hostname based
on the directory.

I don't know enough about hostnames to know what are valid characters,
but in the future this could allow a hostname such as "servers/madoka"
which may be an issue. For now the structure is simple enough of
"hosts/name" resulting in hostname "name"

Another commit is planned which will do the same thing for users

hosts/jibril/host.nix

@@ -0,0 +1,39 @@
+{ config, ... }:
+
+{
+  imports = [
+    ./hardware.nix
+  ];
+  networking.hostName = "jibril";
+  nixpkgs.config.allowUnfree = true;
+  system.stateVersion = "23.05";
+
+  sops-nix = {
+    enable = true;
+    keyFile = "/etc/sops/age/keys.txt";
+    sopsFile = ./secrets.yaml;
+    secrets = {
+      wireless = {};
+    };
+  };
+
+  pipewire.enable = true;
+  polkit.enable = true;
+  bluetooth.enable = true;
+  wireless = {
+    enable = true;
+    networks = builtins.fromTOML (builtins.readFile ./networks.toml);
+    secretsFile = config.sops.secrets.wireless.path;
+  };
+
+  user.name = "pan";
+  user.timezone = "America/Los_Angeles";
+
+  tuigreet.enable = true;
+  hyprland.enable = true;
+
+  librewolf.enable = true;
+  fish.enable = true;
+  fish.setDefault = true;
+  syncthing.enable = true;
+}