fix(client/windows): 修桌面/标题栏图标 + 标题文案 + 系统托盘空白

- app_icon.ico 重新由 assets/app-icon.svg 生成(穿山甲品牌图标,多尺寸),
  替换残留的默认 Flutter logo —— 同时修好桌面图标与标题栏小图标。
- 窗口标题去掉 "VPN" 字眼:main.cpp 原生标题 pangolin_vpn → Pangolin;
  main.dart 用 windowManager.setTitle('穿山甲') 显示中文品牌名;
  Runner.rc 的 FileDescription/InternalName/ProductName → Pangolin。
- 系统托盘空白:Windows 走 Win32 Shell_NotifyIcon 只认 .ico(传 PNG 显示空白),
  新增 BMP 编码的 assets/tray_icon.ico,system_tray.dart 按平台选 ico/png。
- 安装包版本 1.0.0 → 1.0.1(pubspec 1.0.1+2)便于区分测试构建。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client/windows/runner/Runner.rc

@@ -90,12 +90,12 @@ BEGIN
         BLOCK "040904e4"
         BEGIN
             VALUE "CompanyName", "com.pangolin" "\0"
-            VALUE "FileDescription", "pangolin_vpn" "\0"
+            VALUE "FileDescription", "Pangolin" "\0"
             VALUE "FileVersion", VERSION_AS_STRING "\0"
-            VALUE "InternalName", "pangolin_vpn" "\0"
+            VALUE "InternalName", "Pangolin" "\0"
             VALUE "LegalCopyright", "Copyright (C) 2026 com.pangolin. All rights reserved." "\0"
             VALUE "OriginalFilename", "pangolin_vpn.exe" "\0"
-            VALUE "ProductName", "pangolin_vpn" "\0"
+            VALUE "ProductName", "Pangolin" "\0"
             VALUE "ProductVersion", VERSION_AS_STRING "\0"
         END
     END

client/windows/runner/main.cpp

@@ -27,7 +27,7 @@ int APIENTRY wWinMain(_In_ HINSTANCE instance, _In_opt_ HINSTANCE prev,
   FlutterWindow window(project);
   Win32Window::Point origin(10, 10);
   Win32Window::Size size(1280, 720);
-  if (!window.Create(L"pangolin_vpn", origin, size)) {
+  if (!window.Create(L"Pangolin", origin, size)) {
     return EXIT_FAILURE;
   }
   window.SetQuitOnClose(true);