Feature: Add "Online Notify" to log message context menu in main dialog

- Add "Online Notify" menu item to the log message list (m_CList_Message)
  right-click context menu, allowing users to extract IPv4 addresses from
  selected log entries and add them to notification keywords
- Implement ExtractFirstIPFromMessage() for dependency-free IPv4 parsing
  with per-segment 0-255 validation, handling diverse log message formats
- Extend NotifyManager::ShouldNotify with IP column (ONLINELIST_IP)
  fallback check, ensuring IP keywords match regardless of the user's
  configured ColumnIndex setting
- OnMsglogLoginNotify only appends keywords and enables the rule without
  overwriting the user's existing ColumnIndex or TriggerType settings
- Menu item is automatically grayed out when PowerShell is unavailable
  or no log entry is selected
- Sync en_US / zh_TW language files with new translation strings

Co-Authored-By: DeepSeek V4 Pro

server/2015Remote/2015RemoteDlg.h

@@ -564,6 +564,7 @@ public:
     afx_msg void OnMsglogCopy();
     afx_msg void OnMsglogClear();
     afx_msg void OnMsglogSearch();
+    afx_msg void OnMsglogLoginNotify();
     afx_msg void OnOnlineAddWatch();
     afx_msg void OnNMCustomdrawOnline(NMHDR* pNMHDR, LRESULT* pResult);
     afx_msg void OnOnlineRunAsAdmin();