M13: covering what was already claimed

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M12 made the suites continuous. This is about what they were
continuously running, which turned out to be less than the milestones
above claim.

Seven behaviours had no coverage at all. Each is asserted by a milestone
that says "Verified:", and each was — once, by hand, on the machine of
whoever wrote it.

Claimed in	What nothing re-ran
M2	The restart policy firing at all.
M2	The backoff doubling: 200ms, 400ms, 800ms.
M2	on-abnormal treating a signal death as abnormal.
M2 / M3	A watchdog miss taking the restart policy.
M1	%N and %u, against a running machine.
M5	oxctl reload.
M7	output = "null" actually discarding.

flaky.toml is the whole story in one file

It has existed since M2. Its comment describes the doubling exactly:

Exercises on-failure plus backoff: the delays should be 200ms, 400ms,
800ms, ... doubling each time.

And it was never reachable from default, so nothing ever started it. A
unit file that documents a test nobody runs is worse than no unit file,
because it reads as coverage.

The watchdog one is the most interesting

ARCHITECTURE argues at length that a watchdog miss must take the restart
policy where an oxctl stop overrides it, and calls that asymmetry "the
point of a watchdog". The only unit that ever missed a watchdog declared
restart = "no" — so only the half that changes nothing had run.

Nothing was broken

All seven worked the first time they were asked to. That is the honest
result and worth saying plainly: this milestone bought guarding, not
fixing. The code was right; nothing was watching it.

Verified

38 checks per architecture, 40 against the real Alpine userspace, 10 in
the container.

Deferred: the backoff reset after a sustained Active period, which M2
also claims. Telling "reset" from "never incremented" needs an assertion
about a counter's history, and substring matching over a log cannot make
one — it needs a different kind of test than this suite is.