feat(zsh): add zsh as default user shell

modules/nixos/cli/default.nix

@@ -0,0 +1,13 @@
+{config, lib,...}:
+{
+imports = [];
+
+options.cli = {};
+
+config = lib.mkMerge [
+{
+programs.zsh.enable = true;
+environment.pathsToLink = ["/share/zsh"];
+}
+];
+}

modules/nixos/system/users.nix

@@ -2,6 +2,7 @@
 {
   config = lib.mkMerge [
     {
+      users.defaultUserShell = pkgs.zsh;
       users.users."${config.system.mainUser}" = {
         isNormalUser = true;
         initialPassword = "1";