Insecure Update

How insecure update manifest parsing happens in C++ UpdateHelper.cpp and how to fix it

TrafficMonitor's software update mechanism in `UpdateHelper.cpp` fetched and parsed update manifests from remote servers without validating the version string or enforcing trusted download URLs, leaving users exposed to man-in-the-middle (MITM) attacks. An attacker on the same network could intercept the update channel and inject a malicious binary under a crafted version string or an HTTP download link pointing to attacker-controlled infrastructure. The fix adds strict version-string sanitizati