move options back out to their config files, improve documentation

modules/features/applications/gui/kitty.nix

@@ -1,4 +1,8 @@
 { inputs, self, ... }: {
+  imports = [ (inputs.helpers.mkMirroredModulesFlakeModule "graphicsOptions" ({ lib, ... }: {
+    options.features.applications.gui.kitty.enable = lib.mkEnableOption "Kitty Terminal";
+  }))];
+
   flake.nixosModules.graphics = { pkgs, config, lib, ... }: {
     config = let
     in lib.mkIf (config.features.applications.gui.kitty.enable) (inputs.helpers.mkIfElse (config.features.nixos.home-manager.enable) {