pktapdemo is a pure Go implementation of pktap metadata extraction,
equivalent to the C demo pktap_meta_demo.c.
It demonstrates parsing pktap v1 and v2 headers from DLT_PKTAP captures.
Usage:
pktapdemo -i <interface> live capture (macOS: uses pktap mode automatically)
pktapdemo -c <count> max packet count (default 5)