SAFETY-57: the stale-reading verdict gets an exit, because its own consequence is what stopped it being tested

SAFETY-37's freshness gate reports a battery-power register as MISSING when it
stops following its own command, and a missing input is "command 0 W and keep
commanding" (§11.1 rule 1). The gate's only exit was "an arrival carrying a
DIFFERENT number" - and at 0 W nothing is asking the register to be anywhere.
The state had no exit reachable from inside it, and the log line promised the
opposite in the same sentence that announced the 0 W.

REPRODUCED FROM THE WIRE, NOT MODELLED. scenarios/safety57-2026-09-21/ is 3840
verbatim frames off the RS-485 pair, read from the passive sniffer, decoded by
tools/decode_bus_capture.py (0 unparsed, 0 bad CRC, 0 unknown shapes; the
mode->sign convention is graded off the capture, not trusted). The box was
running 0.10.0, so the 0 W in the trace IS the add-on's own claim:

  10:51:24.7  0x0518 reaches -3 W. Pack at 11 %, the BMS refuses the discharge,
              the inverter idles. THE REGISTER IS HEALTHY AND TRUTHFUL.
  10:51:29.7  the command reaches +1060 W - 800 W of travel
  10:52:00    the conjunction arms. Inverter.batt becomes None
  10:52:21.7  the site commands 0 W, on the wire
  ...         0x0518 does not change value for 850.0 s. The setpoint does not
              change value for 790.0 s. The house exports 2.4 kW throughout
  ~11:04      a human restarts the add-on. That is what ends it

AND IT HAD BEEN ESCAPING BY LUCK. Replaying the committed 16-day loop capture
through the shipped conjunction finds 93 trips whose wait for the BMS
keep-alive pulse that cleared them has a median of 143.4 s, a worst case of
21440.1 s, and 17 of 93 at or beyond this episode's 710 s. That distribution
belongs to the battery's firmware, not to this code.

THE CARD'S OPTION 2 ALREADY HELD AND IS NOT THE BUG. _grade() has required
|standing| >= MOVE_W since SAFETY-37. The trip was at +1060 W and the stuck
state is at 0 W; they are different moments, and an entry-side rule cannot
reach a state entered legitimately and then persisted. Nothing in the
conjunction is weakened here.

THE RULE, SAFETY-13's SHAPE ONE MODULE OVER - which latches get an exit, not
how long the block lasts:

  the verdict is withdrawn when the obligation that produced it has been gone
  for RELEASE_S, and the register is then re-graded from scratch.

RELEASE_S is BATT_OBLIGED_S, 17.0 s - the obligation window already derived in
the file (6.0 plant + 10.0 publish + 1.0 read), taken at the FLOOR of its band
for the mirror of MOVE_W's reason. Which half is safe is the opposite of
SAFETY-13's: being wrong long is the failure being fixed, being wrong short
costs one bounded re-grading window. Below 17 s the release pre-empts the
cheaper exit - the register answering by itself - and that is graded
behaviourally, not asserted.

The whole parked interval is now stale_input_s + RELEASE_S = 32 s. On the live
episode: telemetry back at 10:52:39 instead of 11:05:35, with 0x0518 still
answering the same -3 W. RED BEFORE (release_s=inf, a graded counterfactual and
not a second implementation), GREEN AFTER.

WHAT IT COSTS, AND IT IS NOT SMALL. A register dead for good is re-graded for
ever: over 1201 reads the held number reaches a consumer on 630 (52.5 %)
against 35 (2.9 %) before. Payable only because one window is at most 35 s and
the two consumers hold for 75 s and 85 s, so neither can reach a verdict inside
one and the re-trip clears both windows. No detection SAFETY-37 had is given
back - a permanent None clears the same windows for ever too - and the command
is derived from the P1 meter, never from batt.

Two clocks, deliberately: changed_mono/unchanged_s() stay facts about the
REGISTER, graded_from/graded_s() are the VERDICT's window. Collapsing them
either lies to the operator or defeats the re-grading.

main.py's stale line had its ESCAPE CLAUSE corrected - it promised a clearance
the state could not produce - and gained a STALE WITHDRAWN edge that says in
its own words that nothing has been learned about the register. The DIAGNOSIS
half is SAFETY-56's and is deliberately untouched, with a named check asserting
it is still there so that rewrite has to be deliberate.

Battery: 22 mutations, 21 red, 1 argued equivalent, 0 unexplained survivors.
Two findings kept in DECISIONS: _release()'s move_w test swapped for
unchanged_s SURVIVED at +5 B because every fixture rested at exactly 0 W (habit
11, closed by a 0/100/300 W fixture); and the code shipped a habit-22 comment
claiming the _release/_grade order was load-bearing, which the battery
falsified - the two act on mutually exclusive predicates, so the order is not
observable. MUTATION.md gains habit 23 for a mutation that ran, fingerprinted
clean, and was a no-op on the fixture because `0.0 or x` is x.

Suite: 30/30 in the CI image, checks.yml's exact command, purged tree, :ro, one
file at a time.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwRLw7eKYj2byVdwB6kbjU

goodwe_controller/CHANGELOG.md

@@ -231,6 +231,7 @@ Contents of this release, in merge order since 0.9.0 (`86bdf49`):
 | `587495e` | SAFETY-47 - what a shadow run can show you, and the watts on its status row **⚠️ CORRECTS THREE CLAIMS SAFETY-10 SHIPPED** |
 | `660d079` | TEL-10 - the loop's integrator stops being invisible: three new site sensors **⚠️ THREE NEW ENTITIES** |
 | `186a044` | SAFETY-48 - the integrator's lead over the command is bounded at one slew step **⚠️ THE CONTROL LAW CHANGED** |
+| _this branch_ | SAFETY-57 - the stale-reading verdict gets an exit, because its own consequence is what stopped it being tested **⚠️ MEASURED ON THE LIVE SITE** |
 
 ⚠️ **[[CI-9]] ALSO MERGED INTO `release/1.0` IN THIS WINDOW AND IS
 DELIBERATELY NOT IN THE TABLE ABOVE, NOR ANYWHERE ELSE IN THIS FILE.** It
@@ -248,6 +249,82 @@ clean up after - and it is still not an operator-facing change. If a future CI
 ticket changes what the shipped image contains, it belongs here; this one does
 not.
 
+### SAFETY-57 — the stale-reading verdict gets an exit
+
+⚠️ **THIS ENTRY IS FILED UNDER 0.10.0 AND 0.10.0 IS NO LONGER UNSHIPPED, WHICH
+THIS SECTION'S OWN PREAMBLE SAYS IS THE MOMENT TO STOP FOLDING INTO IT.** The
+preamble above, written 2026-09-19, argues that `0.10.0` "does not yet name a
+tree anyone is running" and makes the argument **conditional on that remaining
+true**. It is no longer true: 0.10.0 is on the reference install, and this card
+exists because of a defect **measured on that install on 2026-09-21**. The row
+is here only because `test_version_gate.py` part 11b requires the newest `## `
+heading to be a version rather than `Unreleased`, so a feature branch has
+nowhere else to put one. **Whoever cuts the next version owns moving it**, and
+`tools/predeploy_check.py` will refuse a deploy that folds into a shipped
+0.10.0 by itself.
+
+⚠️ **WHAT IT FIXES, ON THE OWNER'S OWN BATTERY.** [[SAFETY-37]]'s freshness gate
+reports a battery-power register as MISSING when it stops following its own
+command, and a missing input is `command 0 W and keep commanding` (§11.1
+rule 1). The gate's only exit was *"an arrival carrying a different number"* —
+**and at 0 W nothing is asking the register to be anywhere.** The state had no
+exit reachable from inside it, and the log line said the opposite.
+
+Measured off the RS-485 bus, 2026-09-21, and committed as
+`scenarios/safety57-2026-09-21/`:
+
+| | |
+|---|---|
+| 10:51:24 | 0x0518 reaches **−3 W**. The pack is at 11 %, the loop has just reversed out of a charge, and the BMS refuses the discharge. The register is **healthy and truthful**. |
+| 10:51:29 | the command reaches **+1060 W**, 800 W of travel |
+| 10:52:00 | the gate arms. `Inverter.batt` becomes `None` |
+| 10:52:21 | **the site commands 0 W — on the wire, in the capture** |
+| … | the register does not change value for **850 s**. The setpoint does not change value for **790 s**. The house exports 2.4 kW throughout |
+| ~11:04 | **a human restarts the add-on.** That is what ends it |
+
+It had been escaping by luck: the BMS emits a keep-alive pulse that twitches
+the register and satisfies the clearing rule by accident. Replaying the
+committed 16-day loop capture through the shipped conjunction finds **93 trips**
+whose wait for that accident has a **median of 143 s** and a worst case of
+**5 h 57 m**, with **17 of the 93** at or beyond this episode's 710 s. That
+distribution belongs to the battery's firmware, not to this add-on.
+
+**The rule, and it is [[SAFETY-13]]'s shape one module over** — which latches
+get an exit, not how long the block lasts:
+
+> the verdict is withdrawn when the obligation that produced it has been gone
+> for `RELEASE_S`, and the register is then re-graded from scratch.
+
+`RELEASE_S` is **17.0 s**, the obligation window already derived in
+`freshness.py` — 6.0 s of plant, one 10 s ESPHome publish, one 1 s add-on read.
+It is the **floor** of its band rather than a preference: below it the release
+pre-empts the cheaper exit (the register answering by itself), and being wrong
+*long* is the failure being fixed. **The whole parked interval is now
+`stale_input_s` + `RELEASE_S` = 32 s**, bounded by two shipped numbers and by
+nothing the battery does. On the live episode: telemetry back at **10:52:39
+instead of 11:05:35**, with **0x0518 still answering the same −3 W**.
+
+⚠️ **WHAT IT COSTS, AND IT IS NOT SMALL.** A register that is dead for good is
+re-graded for ever. Driven over 1201 reads at the shipped defaults: the held
+number reaches a consumer on **630 reads (52.5 %)** against 35 (2.9 %) before.
+That is payable only because **one re-grading window is 35 s and the two
+consumers hold for 75 s and 85 s** — neither can reach a verdict inside one,
+and the re-trip that ends each window hands them a `None`, which *clears* their
+windows. **No detection SAFETY-37 had is given back**: a permanent `None`
+clears those same windows for ever too. What the site gets back is its
+meter-derived control, and the command was never derived from `batt`.
+
+⚠️ **WHAT YOU WILL SEE.** A new `STALE WITHDRAWN <unit>` line in the action log
+beside the existing `STALE <unit>` one, and a log warning that says in its own
+words that **nothing has been learned about the register**. If the pair repeats
+every ~70 s, the register really is not following and the unit needs looking at;
+if it happens once and stops, the pack was simply empty and the site has
+resumed. The stale line's escape clause was also corrected — it used to promise
+a clearance the state could not produce. ⚠️ Its **diagnosis** half still says
+*"is not following its own command"*, which is wrong in a different way when the
+pack is merely empty; that wording is [[SAFETY-56]]'s and is deliberately
+untouched here.
+
 ### SAFETY-48 — the integrator's lead over the command is bounded, and the control law changed
 
 ⚠️ **THIS CHANGES WHAT THE INVERTER IS ASKED TO DO.** It is the only entry in