fix(ghostty): add cairo wrapper and make it the default terminal

modules/desktop/desktop-entries.nix

@@ -29,7 +29,7 @@ let
     name = "com.mitchellh.ghostty";
     desktopName = "Terminal";
     genericName = "Terminal Emulator";
-    exec = "ghostty";
+    exec = "ghostty-cairo";
     icon = "com.mitchellh.ghostty";
     categories = [
       "System"
@@ -37,7 +37,7 @@ let
       "Utility"
     ];
     terminal = false;
-    comment = "Fast GPU-accelerated terminal";
+    comment = "Terminal (Cairo renderer fallback)";
   };
 in
 {

modules/desktop/gnome-minimal.nix

@@ -50,7 +50,7 @@ in
 
           "org/gnome/shell/extensions/logo-menu" = {
             menu-button-icon-image = lib.gvariant.mkInt32 51;
-            menu-button-terminal = "ghostty";
+            menu-button-terminal = "ghostty-cairo";
             menu-button-system-monitor = "missioncenter";
             menu-button-extensions-app = "com.mattjakeman.ExtensionManager.desktop";
             hide-softwarecentre = true;

modules/system/packages.nix

@@ -1,5 +1,11 @@
 { lib, pkgs, ... }:
 
+let
+  ghosttyCairo = pkgs.writeShellScriptBin "ghostty-cairo" ''
+    export GSK_RENDERER=cairo
+    exec ghostty "$@"
+  '';
+in
 {
   # Baseline system tools available everywhere; users run Home Manager standalone.
   config.environment.systemPackages = lib.mkAfter [
@@ -11,6 +17,7 @@
     pkgs.fastfetch
     pkgs.flatpak
     pkgs.ghostty
+    ghosttyCairo
     pkgs.git
     pkgs.home-manager
     pkgs.just

modules/system/shell.nix

@@ -24,9 +24,11 @@ in
   ];
 
   # Use Ghostty as the default terminal emulator.
+  # On some machines Ghostty may fail to acquire an OpenGL context; `ghostty-cairo`
+  # forces GTK4's Cairo renderer (CPU) and is more hardware-agnostic.
   environment.sessionVariables = {
-    TERMINAL = "${pkgs.ghostty}/bin/ghostty";
-    DEFAULT_TERMINAL = "${pkgs.ghostty}/bin/ghostty";
+    TERMINAL = "ghostty-cairo";
+    DEFAULT_TERMINAL = "ghostty-cairo";
   };
 
   programs.bash = {