refactor: modules/gui/default.nix: fold into hosts/modules/gui/default.nix

hosts/modules/gui/default.nix

@@ -1,4 +1,9 @@
-{ ... }:
+{ lib, config, ... }:
+
+let
+  inherit (lib) mkDefault mkIf mkOption types;
+  cfg = config.sane.gui;
+in
 {
   imports = [
     ./gnome.nix
@@ -7,4 +12,24 @@
     ./plasma-mobile.nix
     ./sway.nix
   ];
+
+  options = {
+    sane.gui.enable = mkOption {
+      default = false;
+      type = types.bool;
+      description = ''
+        enables config used by any GUI, like display management or select packages.
+        the user should prefer to interact with specific GUIs like `sane.gui.sway`
+        and let those modules auto-set this flag when necessary.
+      '';
+    };
+  };
+
+  config = mkIf cfg.enable {
+    sane.packages.enableGuiPkgs = mkDefault true;
+
+    # preserve backlight brightness across power cycles
+    # see `man systemd-backlight`
+    sane.persist.sys.plaintext = [ "/var/lib/systemd/backlight" ];
+  };
 }

modules/default.nix

@@ -4,7 +4,6 @@
   imports = [
     ./feeds.nix
     ./fs
-    ./gui
     ./home-manager
     ./ids.nix
     ./packages.nix

modules/gui/default.nix

@@ -1,23 +0,0 @@
-{ lib, config, ... }:
-
-with lib;
-let
-  cfg = config.sane.gui;
-in
-{
-  options = {
-    # doesn't directly create outputs. consumed by e.g. home-manager.nix module
-    sane.gui.enable = mkOption {
-      default = false;
-      type = types.bool;
-    };
-  };
-
-  config = lib.mkIf cfg.enable {
-    sane.packages.enableGuiPkgs = lib.mkDefault true;
-
-    # preserve backlight brightness across power cycles
-    # see `man systemd-backlight`
-    sane.persist.sys.plaintext = [ "/var/lib/systemd/backlight" ];
-  };
-}