- Set QUIC InitialPacketSize per IP family (IPv4: 1252, IPv6: 1232)
- Set MaxIncomingStreams/MaxIncomingUniStreams to 1<<60
- Populate OriginLocalIP from local socket address in both QUIC and HTTP/2
- Pass NumPreviousAttempts from retry counter to registration
- Include version number in client version string
- Use OS_GOARCH format for Arch field