Switch to using sddm for hyprland

Add catppuccin-corners theme

system/desktop.nix

@@ -6,6 +6,7 @@
     libnotify
     glib
     gsettings-desktop-schemas
+    catppuccin-sddm-corners
   ];
   security.rtkit.enable = true;
   sound.enable = true;
@@ -21,8 +22,14 @@
       pulse.enable = true;
     };
     xserver = {
+      enable = true;
       layout = "gb";
       xkbVariant = "";
+      displayManager.sddm = {
+        enable = true;
+        theme = "catppuccin";
+        settings = { General = { InputMethod = ""; }; };
+      };
     };
   };
   console.keyMap = "uk";

system/hyprland.nix

@@ -22,18 +22,9 @@
     blueman.enable = true;
     gvfs.enable = true;
     tumbler.enable = true;
-    greetd = {
-      enable = true;
-      settings = {
-        default_session = {
-          inherit user;
-          command = "Hyprland";
-        };
-        initial_session = {
-          inherit user;
-          command = "Hyprland";
-        };
-      };
+    xserver.displayManager = {
+      sessionPackages = [ hyprland.packages.${pkgs.system}.hyprland ];
+      defaultSession = "hyprland";
     };
   };
   fonts = {