test(publish-smoke): judge the boot before the probes run (#16976)

* test(publish-smoke): judge the boot before the probes run

The registry canary could not name a WARN-level boot failure. Two properties
of the server-log scan combined:

  * SEVERITY - a plugin that fails to load logs at WARN, and the scan matched
    error|fatal only.
  * ORDER - the scan is the last thing in the script, after the probes, so
    even at a matching severity a boot defect was reported as a probe failure
    first.

Measured on the specimen (run 34084559243): the pre-fix pattern matches ZERO
lines in that boot window, after which the job probed every auth and CRUD
route against a server with no auth and failed on a probe, naming nothing.
A boot-load failure and an auth regression have different owners and produced
the same job output.

Adds a boot gate between sections 2 and 3 - the same shape the audience-posture
assertion already uses, which fails before the behaviour probes for the same
reason. Section 4 is NOT hoisted: it stays after the probes and keeps catching
what they provoke.

The predicate is severity-blind and keys on the sentence: a unit of the
composition did not arrive. Widening to WARN was rejected against a measured
healthy baseline - pack run 34276056630 boots healthily while emitting
`Console dist not found` behind the same warn glyph the specimen uses.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012GKcPZbMoGq7WPzKLfRBTU

* test(publish-smoke): add a registry-mode healthy boot to the firing control

The pack-mode healthy fixture could not catch the mistake the predicate exists
to avoid. Measured, not foreseen: under a deliberately wrong `WARN|warn`
predicate the firing control stayed GREEN, because that fixture's only
warn-shaped line carries the glyph and never the word.

Registry mode installs the last published release, so a protocol-floor
conversion warning is normal there and arrives as a full `<ISO>Z WARN ...`
line. Asserting a healthy boot that spells WARN in full is what turns "do not
widen the severity set wholesale" into something this file can redden on.

The fixture is reconstructed rather than verbatim - the specimen's own boot
window with the four lines attributable to the defect removed - and its
docblock says so.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012GKcPZbMoGq7WPzKLfRBTU

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Co-authored-by: Claude <noreply@anthropic.com>

Author: claude[bot]