refactor(nixos): inline module enable conditions

configs/nixos/modules/desktop/session/hyprland/hyprlock.nix

@@ -6,7 +6,6 @@
 }:
 # The lock screen: a hyprlock session-lock surface the compositor owns.
 let
-  cfg = config.modules.desktop.session.hyprland.hyprlock; # NOLINT(let_order)
   user = config.user.name;
 
   # The hyprlock this module installs, used by the lock keybind below.
@@ -48,7 +47,7 @@ in
   options.modules.desktop.session.hyprland.hyprlock.enable =
     lib.mkEnableOption "the hyprlock lock screen";
 
-  config = lib.mkIf cfg.enable {
+  config = lib.mkIf config.modules.desktop.session.hyprland.hyprlock.enable {
     home-manager.users.${user} = {
       # Colors and the lock-screen background come from Stylix's hyprlock target,
       # so only geometry and behaviour are set here.