meta: Remove gamemode

As far as I can tell, there isn't any noticeable performance difference
with the hardware I use.

modules/default.nix

@@ -5,7 +5,6 @@
     ./dual-function-keys.nix
     ./fish.nix
     ./fonts.nix
-    ./gamemode.nix
     ./greetd.nix
     ./home-manager.nix
     ./hyprland.nix

modules/gamemode.nix

@@ -1,19 +0,0 @@
-{ pkgs, ... }:
-
-{
-  programs.gamemode = {
-    enable = true;
-
-    settings = {
-      general = {
-        renice = 10;
-        igpu_power_threshold = -1;
-      };
-
-      custom = {
-        start = "${pkgs.libnotify}/bin/notify-send 'Note' 'gamemode started from host.'";
-        end = "${pkgs.libnotify}/bin/notify-send 'Note' 'gamemode ended from host.'";
-      };
-    };
-  };
-}

setup.nix

@@ -5,7 +5,6 @@
     ./overlays
     ./modules/fish.nix
     ./modules/fonts.nix
-    ./modules/gamemode.nix
     ./modules/home-manager.nix
     ./modules/locale.nix
     ./modules/neovim.nix