feat(gnome-wayland): 添加自动关闭Xwayland功能

新增 autoclose-xwayland 选项，当所有相关的X11客户端消失时自动终止Xwayland，
以优化资源使用和系统性能。

Author: DataEraserC

home/linux/gui/gnome-wayland/values/gnome.nix

@@ -36,6 +36,7 @@ in
         "scale-monitor-framebuffer" # Enables fractional scaling (125% 150% 175%)
         "variable-refresh-rate" # Enables Variable Refresh Rate (VRR) on compatible displays
         "xwayland-native-scaling" # Scales Xwayland applications to look crisp on HiDPI screens
+        "autoclose-xwayland" # automatically terminates Xwayland if all relevant X11 clients are gone
       ];
     };
     # 挂起恢复有问题