显卡鉴定指南改为原版纸质指南样式（9 页、插图、折价标注、鉴定示例），8 种语言

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/Decentralized/HandbookWindow.cs

@@ -46,7 +46,6 @@ namespace Decentralized
         private static readonly Dictionary<string, int> _chapterOf = new Dictionary<string, int>();
 
         public static void Open() => Show("guide.web3.text", "item.web3guide.name");
-        public static void OpenGpu() => Show("guide.gpu.text", "item.guide.name");
 
         private static void Show(string key, string nameKey)
         {