- Upgrade Go version from 1.21 to 1.25.0
- Update golang.org/x/sys dependency to v0.42.0
- Add Unix/Linux admin check using os.Geteuid() with sudo requirement
- Add Windows admin check using windows.SID and token membership validation
- Integrate admin privilege validation into main CLI entry point
- Enhance monitor.go with graceful signal handling for Ctrl+C interrupts
- Add signal channels for clean shutdown of monitoring loop
- Ensures VPN client runs with required elevated privileges on both platforms
