flyedge.service runs /opt/fly/current/fly-edge After= and Requires=
flysim.service, with its metrics on loopback :9102 and a
ConditionPathExists so a release without the binary leaves it inactive. It is
in no target and 07-enable.sh does not enable it; the header has the switch
and the way back.
build-flysim.sh also builds fly-edge beside the flysim binary and
package-release.sh ships it when present. 05-deploy.sh writes
FLY_FEED_VIA (default direct) into fly.env, flysim.service names
FLY_BUS_DIR=/run/fly/bus and tmpfiles creates it. Watchdog check 2 reads the
feed counters from whoever serves the feed: flyedge when fly.env says bus.
lint.sh holds all of that, and drives check 2's choice against a fixture.
