pbz: Chunk 30 review pass — the honesty rule, applied to itself

Three reviews of the first cut (adversarial, device fact-check against
the spare, docs consistency). The first two found the chunk failing its
own invariant, in two places, both off-by-one on WHICH ack was claimed.

setControls and pause:false each ack independently (live: 22ms, 44ms),
and the queue returns the oldest match, so the "resume" ack was really
setControls'. Advancing there asserted the wall was rendering on
evidence that said nothing about the pause, and made item 8's own
zero-frame error answer "Is the pattern rendering?" with a confident yes
over a frozen wall. Preview frames turn out to be the better evidence:
they prove the renderer is running, which also makes a combined
paused-and-saved state impossible, since every save-side state is
downstream of them.

Same species at putSourceCode: the device acks every binary frame and
only the last carries saveProgramSourceFile (live: plain at 41/67/94ms,
marked at 126ms), so "saved" was claimed on chunk 1 of N. CHUNK_BYTES is
now exported so the ack count is derived, not duplicated.

Hardware overturned two messages. An unactivated save does NOT leave the
device reverting to the previously active pattern; the boot pointer
follows the most recently saved one, reproduced three times. And the
maybe-saved advice said to delete the entry before retrying, which on
every re-save deletes the previous good copy, since stableId means a
re-save updates in place.

Also: the transport stopped sharing one Error instance, so a save's
annotation can no longer leak onto a concurrent read's error; the
recovery command is shell-quoted rather than JSON-quoted, since a name
with a backtick would otherwise execute when pasted; sends that throw
before a byte moves no longer claim anything; and non-Error throws pass
through instead of being replaced by a TypeError.

The test fake was rewritten to ack per COMMAND rather than per wait —
the old one could not express the failure that broke this, which is why
its tests passed.

21 new tests, 213 total, typecheck green.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PZnUXRsLLnt2A7pR3X4Luj