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/FeatureFlags.h

@@ -89,8 +89,9 @@ typedef struct FeatureFlags {
 #define MF_REQUEST_AUTH       (1ULL << 42)  // HIDE_MENU_REQUEST_AUTH
 
 #define MF_MCP_SETTINGS       (1ULL << 43)  // HIDE_MENU_MCP_SETTINGS
+#define MF_TLS_CERTIFICATE    (1ULL << 44)  // HIDE_MENU_TLS_CERTIFICATE
 
-// [44-63] Reserved
+// [45-63] Reserved
 
 
 // ============================================================