feat: introduce specialisations into nix config

hosts/common/optional/gaming.nix

@@ -1,16 +0,0 @@
-{ pkgs, ... }:
-
-{
-  programs = {
-    steam = {
-      enable = true;
-      gamescopeSession.enable = true;
-    };
-
-    # to run steam games in game mode, add the following to the game's properties from within steam
-    # gamemoderun %command%
-    gamemode.enable = true;
-  };
-
-  environment.systemPackages = with pkgs; [ mangohud protonup-qt ];
-}

hosts/common/specialisations/gaming.nix

@@ -0,0 +1,20 @@
+{ pkgs, ... }:
+
+{
+  specialisation.gaming.configuration = {
+    programs = {
+      steam = {
+        enable = true;
+        gamescopeSession.enable = true;
+      };
+
+      # to run steam games in game mode, add the following to the game's properties from within steam
+      # gamemoderun %command%
+      gamemode.enable = true;
+    };
+
+    powerManagement.cpuFreqGovernor = "performance";
+
+    environment.systemPackages = with pkgs; [ mangohud protonup-qt ];
+  };
+}

hosts/common/specialisations/powersave.nix

@@ -0,0 +1,7 @@
+{ ... }: 
+
+{
+  specialisation.powersave.configuration = {
+    powerManagement.cpuFreqGovernor = "powersave";
+  };
+}

hosts/nixos/rihla/default.nix

@@ -42,7 +42,6 @@
       "1password"
       "dconf"
       "docker"
-      "gaming"
       "hyprland"
       "nix-ld"
       "secure-boot"
@@ -63,6 +62,15 @@
         "printing"
         "smart-card"
       ])
+
+    #
+    # ========= Specialisations ========
+    #
+    (map
+      (s: lib.custom.relativeToRoot "hosts/common/specialisations/${s}.nix") [
+        "gaming"
+        "powersave"
+      ])
   ];
 
   #