container@.service sets Restart=on-failure and no start limit, so systemd's
defaults applied: 5 starts per 10s with RestartSec 100ms. That made the bound
a function of how fast a container dies -- one failing instantly tripped the
limit in under a second, one taking longer than ~2s never tripped it and
restarted forever.
The per-container drop-in already carried both sections this needs, so the
bound goes there rather than into a second file. StartLimit* are [Unit]
settings; systemd silently ignores them under [Service], which the pinned
body test now guards.
The values are hive-wide constants rather than wire fields: the bound is
policy, identical for every agent, and threading it through the socket as a
per-agent parameter would be plumbing for a value nobody varies.
Giving up is safe to make tight because it is not terminal -- reconcile
retries later, and the reset-failed already done before each start clears
the latch first.