wallust: fix wallust.toml generation

home/modules/hyprland/wallust/default.nix

@@ -1,8 +1,9 @@
-{ pkgs
-, unstable
-, lib
-, config
-, ...
+{
+  pkgs,
+  unstable,
+  lib,
+  config,
+  ...
 }:
 let
   cfg = config.profile.hyprland;
@@ -56,10 +57,10 @@ in
       (getExe initWallPaperScript)
     ]);
 
-
     # See https://codeberg.org/explosion-mental/wallust/src/branch/master/wallust.toml
     home.file.".config/wallust/wallust.toml".source = (
-      (pkgs.formats.toml { }).generate "wallust.toml"
+      (pkgs.formats.toml { }).generate "wallust.toml" (
+        lib.attrsets.mergeAttrsList [
           {
             backend = "kmeans";
             color_space = "lch";
@@ -67,7 +68,10 @@ in
             threshold = 1;
             palette = "dark";
             checkContrast = true;
-        } // cfg.wallust.settings
+          }
+          cfg.wallust.settings
+        ]
+      )
     );
   };
 }