Launcher - Fix false flag virus detection by Windows defender

[Tapawingo]

When merged this PR will:

• Add named mutex Global\TrenchKitRunning creation at startup
• Add mutex cleanup before exit
• Remove #include <tlhelp32.h> from updater (no longer needed)
• Replace isProcessRunning() + waitForProcessExit() with waitForAppExit() using mutex wait
• Close Bug - Application falsly flagged as virus #61

The updater no longer uses CreateToolhelp32Snapshot to enumerate all running processes (a technique commonly associated with malware). Instead, it simply waits for a named mutex that the main app holds while running.