The default route manager logs for each entry relevant information,
in a compact but cryptic way:

  default-route: entry[0/dev:0x5633d5528560:enp0s25:1:+sync]: record:add    0.0.0.0/0 via 192.168.0.1 dev 2 metric 100 mss 0 rt-src user (100)

The flag whether a route is configured or not, was only expressed
via 0|1. Change that to log instead:

  default-route: entry[0/dev:0x5633d5528560:enp0s25:+has:+sync]: record:add    0.0.0.0/0 via 192.168.0.1 dev 2 metric 100 mss 0 rt-src user (100)