1fad3ab869
Reads the default gateway from the route table: cat /scheme/netcfg/route/gateway → 'default via 192.168.1.1\n' or 'no default route\n' if no default gateway configured. Looks up the route for 0.0.0.0 (the default route CIDR) and returns its 'via' address. Mirrors Linux 'ip route show default'.