game-mods: init

Add override for fh5 startup video

hosts/yarn/default.nix

@@ -15,6 +15,7 @@
     ./impermanence.nix
     ./lact.nix
     ./vr.nix
+    ../../modules/desktop-game-mods.nix
 
     inputs.impermanence.nixosModules.impermanence
   ];
@@ -77,4 +78,16 @@
 
   # yarn is not a Steam Deck
   jovian.devices.steamdeck.enable = false;
+
+  # Skip the 40 MB T10/Microsoft Studios intro video on startup.
+  # The module discovers FH5's install path from Steam's library metadata
+  # and replaces the BK2 file with a 0-byte stub. Re-applies daily via
+  # systemd timer so Steam verify/updates don't silently undo it.
+  services.gameMods = {
+    enable = true;
+    mods."fh5-no-intro" = {
+      steamAppId = 1551360;
+      files."media/UI/Videos/T10_MS_Combined.bk2".empty = true;
+    };
+  };
 }