add gamemode configuration and cleanup the gaming config a bit

nixos/configuration.nix

@@ -111,6 +111,7 @@
       "networkmanager"
       "wheel"
       "docker"
+      "gamemode"
     ];
     openssh = {
       authorizedKeys.keys = [

nixos/gaming.nix

@@ -2,11 +2,35 @@
 {
   programs.steam = {
     enable = true;
+    protontricks.enable = true;
     remotePlay.openFirewall = true; # Open ports in the firewall for Steam Remote Play
     dedicatedServer.openFirewall = true; # Open ports in the firewall for Source Dedicated Server
   };
+  programs.gamemode = {
+    enable = true;
+    enableRenice = true;
+    settings = {
+      general = {
+        renice = 10;
+        inhibit_screensaver = 1;
+      };
+      filter = {
+        # whitelist = ''
+        #   RiseOfTheTombRaider
+        # '';
+
+        # blacklist = ''
+        #   HalfLife3
+        #   glxgears
+        # '';
+      };
+      custom = {
+        start = "${pkgs.libnotify}/bin/notify-send 'GameMode started'";
+        end = "${pkgs.libnotify}/bin/notify-send 'GameMode ended'";
+      };
+    };
+  };
   environment.systemPackages = with pkgs; [
-    gamemode
     (prismlauncher.override {
       jdks = with pkgs; [
         jdk8
@@ -17,7 +41,6 @@
     lunar-client
     heroic
     protonup-qt
-    protontricks
     winetricks
     celeste64
   ];