nixos: create 'modules/nixos' folder

Let's consolidate all modules under one path, so that NixOS,
home-manager, and nix-darwin (if I ever end up using it down the line)
would go under the same folder.

modules/nixos/home/default.nix

@@ -0,0 +1,29 @@
+{ config, inputs, lib, ... }:
+let
+  actualPath = [ "home-manager" "users" config.my.user.name "my" "home" ];
+  aliasPath = [ "my" "home" ];
+
+  cfg = config.my.user.home;
+in
+{
+  imports = [
+    inputs.home-manager.nixosModules.home-manager # enable home-manager options
+    (lib.mkAliasOptionModule aliasPath actualPath) # simplify setting home options
+  ];
+
+  config = lib.mkIf cfg.enable {
+    home-manager = {
+      # Not a fan of out-of-directory imports, but this is a good exception
+      users.${config.my.user.name} = import "${inputs.self}/home";
+
+      # Nix Flakes compatibility
+      useGlobalPkgs = true;
+      useUserPackages = true;
+
+      # Forward inputs to home-manager configuration
+      extraSpecialArgs = {
+        inherit inputs;
+      };
+    };
+  };
+}