feat: sway configuration

- Change the mod key to Alt.
- Change the keyboard input language to UK.
- Replace dmenu with wofi.
- Disable the laptop screen when used in clam mode (lid closed with an
  external monitor).
- Override the GTK theme to ensure that a dark theme is used in all apps
  (e.g. Firefox).

See:

- https://github.com/swaywm/sway/wiki#clamshell-mode
- https://wiki.archlinux.org/title/Sway#Keymap

home-manager/nixedo.nix

@@ -36,5 +36,5 @@
     };
   };
 
-  home.packages = with pkgs; [ discord meslo-lg slack teams vlc xcape zoom-us ];
+  home.packages = with pkgs; [ discord meslo-lg slack teams vlc wofi xcape zoom-us ];
 }