home: move zsh and direnv to new modules

home-manager/templates/module.default.nix

@@ -0,0 +1,10 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let cfg = config.modules.X;
+in {
+  options.modules.X = { enable = mkOption { default = false; }; };
+
+  config = mkIf cfg.enable { };
+}