Feature: Add language-switch toolbar button and bilingual dialog

Add a 15th toolbar button "Lang/语言" after the Help button so Chinese
readers can switch language without knowing English; it opens the existing
language-select dialog. The dialog title is now bilingual ("切换语言 /
Switch Language") and its label/buttons use Chinese source strings
("语言:", "确定", "取消"), which still localize to en/de via
TranslateDialog. The toolbar bitmap is extended with a globe icon.

Co-Authored-By: deepseek-v4-pro

server/2015Remote/2015RemoteDlg.cpp

@@ -1409,6 +1409,7 @@ VOID CMy2015RemoteDlg::CreateToolBar()
     m_ToolBar.SetButtonText(11, _TR("生成服务端"));
     m_ToolBar.SetButtonText(12, _TR("搜索"));
     m_ToolBar.SetButtonText(13, _TR("帮助"));
+    m_ToolBar.SetButtonText(14, _T("Lang/语言"));
 
     // ============================================================
     //  UIBranding: 根据编译时配置或运行时标志隐藏工具栏按钮
@@ -1459,7 +1460,7 @@ VOID CMy2015RemoteDlg::CreateToolBar()
     }
 
     // 如果所有按钮都被隐藏，则隐藏整个工具栏
-    if (hiddenCount >= 14) {
+    if (hiddenCount >= 15) {
         m_ToolBar.ShowWindow(SW_HIDE);
     }