Virtucomp SpeedTest Agent Installer v4

Run install_virtucomp_speedtest_agent.bat as Administrator.

What it does:
- Installs Python 3.12 automatically if missing
- Installs Python dependencies
- Prompts for customer/site/API settings
- Writes config to C:\ProgramData\Virtucomp\SpeedTestAgentProd1\config.json
- Installs the agent as a Windows service
- Starts the service
- Registers the device to the server

Notes:
- Supports Windows 11, Windows 10, and Windows Server where Python 3.12 x64 can be installed.
- Uses direct Python executable discovery after install, so it avoids the Microsoft Store alias problem.
- Run as Administrator.
