Connects to a relay over QUIC with SNI "version", reads build hash
from a unidirectional stream, prints "<relay> <git-hash>" and exits.
Usage: wzp-client --version-check 172.16.81.175:4434
Output: 172.16.81.175:4434 8dbda3e
Relay side: detects "version" SNI, opens uni stream, writes
BUILD_GIT_HASH, waits 100ms for client to read, closes.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>