feat(reality): add autodetect command for decoy server

Add REALITY decoy server auto-detection with two scanning modes:
subnet scan (/24 around server IP) and domain list scan.
- Add vless autodetect CLI command with --write flag to update config.
- Add domain list mode for custom target selection.
- Add public IP detection via external services.
- Update install.sh to auto-configure REALITY with --vless flag.
- Track TLS handshake latency in ScanResult for best server selection.