Feat: TLS certificate menu and config dialog for the MFC server

Add a "TLS证书" item to the Extensions menu below "MCP设置" that opens a
runtime-built dialog to enable one-way TLS and set the certificate and
private-key paths. On OK it writes the [tls] Enabled/CertPath/KeyPath keys
and calls ServerTlsIdentity::Load() so the change takes effect for new
connections immediately (design doc §7.1), mirroring the existing
CMcpSettingsDlg runtime-template pattern. All new strings are wired into
the en_US / zh_TW / de_DE language files, and the menu item is gated by
HIDE_MENU_TLS_CERTIFICATE / MF_TLS_CERTIFICATE like MCP settings.

Co-Authored-By: deepseek-v4-pro

server/2015Remote/2015RemoteDlg.h

@@ -696,6 +696,7 @@ public:
     afx_msg void OnCancelShare();
     afx_msg void OnWebRemoteControl();
     afx_msg void OnMcpSettings();
+    afx_msg void OnTlsCertificate();
     afx_msg void OnConnectionManage();
     afx_msg void OnProxyPortAutorun();
     afx_msg void OnScreenpreviewLoop();