SAFETY-52 review: a refusal is under 100 W, and any delivery ends it

- Engage (and seed from a stale stop) below REFUSED_BELOW_W, the probe's
  own 100 W answer, not below saturation_w: a battery derated to 100-499 W
  was held at 0 W ~93 % of the time.
- A reading of 100 W or more in the held direction ends the refusal, probe
  or not: at a 1 s meter SETTLE_CYCLES is 12 s, shorter than a healthy
  reading's lag, and that held a healthy step at 0 W until the next probe.
- test_refusal part 5b and a seed test; DOCS states the N>1 limit; the
  DECISIONS record carries the traced cause of the replay's extra trips.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

goodwe_controller/DOCS.md

@@ -538,17 +538,23 @@ accumulator is doing:
 | `saturated-freeze` | the inverter is not following, so the command's magnitude may fall but not rise |
 | `freeze-released` | the freeze had run out of plant-shaped explanations and the command was let move again |
 | `not-running` | control is stopped **and** shadow mode is off, so the loop did not run |
-| `battery refuses` | the battery gave nothing for a minute while asked for more than 500 W, so the add-on asks 0 W in that direction (see below) |
+| `battery refuses` | the battery gave less than 100 W for 12 cycles (a minute at a 5-second meter) while asked for more than 500 W, so the add-on asks 0 W in that direction (see below) |
 | `battery probe` | the add-on asks 200 W to test whether a refusing battery gives power again |
 
 **When the battery refuses.** At its cut-out level the battery gives nothing,
 whatever it is asked. The add-on then asks 0 W instead of repeating its last
 request, and the `Why` row reads *The battery refuses to give power: 0 W*. Every
-15 minutes it asks 200 W for about half a minute; if the battery answers,
-control resumes. It also resumes when the grid needs charging instead, and when
+15 minutes it asks 200 W for about half a minute. Control resumes as soon as
+the battery gives 100 W or more, when the grid needs charging instead, and when
 control is stopped or started. 200 W is below the 250 W the stale-reading check
-needs, so a test never trips it. One inverter only: with several, the battery
-level limit already moves an empty battery's share to the others.
+needs, so a test never trips it. A battery that gives some power, even 100 W,
+is not refusing and keeps its request.
+
+⚠️ **One inverter only.** With several inverters this hold is off. There, the
+battery level limit moves an empty battery's share to the others, but only if
+its “Battery cut-out level” matches where the battery really stops. A battery
+that refuses at another level, or for another reason (cold, a battery fault),
+can still hold its last request until the grid starts to export.
 
 *For installers:* SAFETY-52. The event log reads `BATTERY REFUSES …` and
 `BATTERY REFUSES ENDED: …`, and the INFO line ends in `BATTERY_REFUSES`.