add(apps): mod organizer 2 added for fallout 4

apps/mo2/default.nix

@@ -0,0 +1,5 @@
+{
+  imports = [
+    ./fallout4.nix
+  ];
+}

apps/mo2/fallout4.nix

@@ -0,0 +1,15 @@
+{myConfig, ...}: {
+  xdg.desktopEntries.mo2-nix-fo4 = {
+    name = "Mod Organizer 2 NXM Handler";
+    exec = "protontricks-launch --appid 377160 \"/home/${myConfig.nixos.username}/Games/mod-organizer-2-fallout4/modorganizer2/ModOrganizer.exe\" %u";
+    terminal = false;
+    categories = ["Game"];
+    mimeType = ["x-scheme-handler/nxm" "x-scheme-handler/nxm-protocol"];
+  };
+
+  xdg.mimeApps.enable = true;
+  xdg.mimeApps.defaultApplications = {
+    "x-scheme-handler/nxm" = ["mo2-nix-fo4.desktop"];
+    "x-scheme-handler/nxm-protocol" = ["mo2-nix-fo4.desktop"];
+  };
+}