feat: add "ubuntu" config for containers

flake.nix

@@ -49,6 +49,27 @@
             ./horsch.nix
           ];
 
+          extraSpecialArgs = {
+            user = "mmandl";
+            userName = "Michael Mandl";
+            userEmail = "michael.mandl@horsch.com";
+            gpgSigningKey = "088ED38F036C7AF2";
+            gpgSSHKeys = [ "AEB2BF3FF9CF9529E9A3C6F1A202D21686FF9278" ];
+            theme = "dark";
+            vimwikiPath = "~/vimwiki";
+          };
+        };
+        "ubuntu" = home-manager.lib.homeManagerConfiguration {
+          inherit pkgs;
+
+          modules = [
+            ./shell
+            ./git
+            ./gpg
+            ./neovim
+            ./horsch.nix
+          ];
+
           extraSpecialArgs = {
             user = "mmandl";
             userName = "Michael Mandl";