TEL-12: several PV inverters, and one absent member is an absent TOTAL

0.11.0 shipped `pv_entity` as a single string. The reference site's owner
reported within minutes of it going live that they have several PV inverters
and could configure one - which is ordinary for a multi-string roof, not a
property of one house. `pv_entities` is the roster and the row carries the
SITE total.

⚠️ THE HARD PART IS ABSENCE, NOT THE LIST. Three configured, one `unavailable`,
and the sum of the other two is a SMALLER NUMBER INDISTINGUISHABLE FROM A REAL
ONE. Read back by OPT-10 that says "there was less PV than there was" - the "no
irradiance" conclusion the channel exists to TEST. So `pv.total()` answers
`None` the moment any configured entity is absent: the topic carries HA's own
`None`, the entity goes to `unknown`, the recorder records a GAP. The
alternative (the partial sum beside a contributor count) was implemented and
run as mutation N1b; it loses because the MQTT row is read COLD a week later by
an attribution that would believe it, while the qualifying count would live in a
second entity with its own history. The partial information is not thrown away -
the STATUS PAGE names every entity that reported, with its watts, and every one
that did not, with its reason, because that surface is read LIVE by a human who
wants the diagnostic.

⚠️ AND THE MIRROR: a member honestly reporting 0 W is SUMMED. The test is
`is None`, never falsiness - a roster that blanked the site on a zero would
report an absence on every clear evening.

THE SURFACE IS MEASURED, NOT PREFERRED. `pv_entity` could not become a list:
tools/supervisor_shape_probe.py §G shows Supervisor 2026.08.0 answering an
0.11.0 install's stored string with `Invalid list for option 'pv_entity'`, and
deepmerge's list strategy is `override` so a `[]` default does not rescue it -
the live add-on would not start. `match(.*)?` does accept both shapes and is
rejected for a different, measured reason: it validates nothing (a string, a
list and the integer 417 all pass) and renders as a plain text box. So
`pv_entities` joins `pv_entity` and REPLACES it when set, CFG-04's rule for
`inverters:`, with a status caution saying which key won - a union would
double-count the inverter the old key still names.

STILL NOT A CONTROL INPUT. tools/tel11_pv_trace.py was extended rather than
replaced and now grades five claims over three document sets. The control hash
is UNMOVED - 846a10a5b89e… on `unset` and on `one`, on both trees - and the
roster control document is byte-identical between the two trees. 2/5 is a claim
TEL-11 could not make: with 0.11.0 as the baseline, "one entity behaves exactly
as 0.11.0 does" is a real cross-tree identity over control AND telemetry.

⚠️ TEL-11's OWN `--compare` REFUSAL HAD TO CHANGE, and that is MUTATION.md habit
24: a discriminator defined as "the baseline lacks this feature" dies on the
release that ships the feature, and dies as a false refusal.

Twelve mutations, each on a fresh purged `cp -a`, no survivors. N5 is +0 B
(`sum` -> `max`, the same three characters) and was run on a fresh copy with
`cmp` confirming the edit on disk. The fixture is three distinct NON-ZERO
contributions in two units with absence driven at EVERY position - a member
contributing 0 W could go absent without moving the sum of the rest, which is
habit 23 with a coinciding value in the arithmetic rather than in the plant.

31/31 in the CI image. Not deployable as merged: config.yaml stays at 0.11.0,
so predeploy_check.py reports a NO-OP until PKG cuts a version. A CHANGELOG
entry is wanted and deliberately not written - 11b forbids `## Unreleased` and
the bump is PKG's call; DECISIONS/TEL-12-several-pv-inverters.md is the
material it needs.

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

goodwe_controller/test_mqtt.py

@@ -716,8 +716,13 @@ print("\n8. verified by breaking it")
 # ---------------------------------------------------------------------------
 # ⚠️ MUTATED SOURCE, EXEC'D INTO A FRESH NAMESPACE. No file is edited and no
 # `.pyc` is consulted, so TEST-15's stale-bytecode failure cannot produce a
-# false survivor here. `app/mqtt.py` imports nothing from this package, which is
-# what makes exec'ing it standalone honest rather than a stub.
+# false survivor here. `app/mqtt.py` imports nothing from this package AT MODULE
+# SCOPE, which is what makes exec'ing it standalone honest rather than a stub.
+# ⚠️ TEL-12 IS WHY THAT NOW SAYS "AT MODULE SCOPE". `optional_keys()` reads
+# `pv.entities()` - one spelling of the roster predicate for the announcement and
+# for the SUM alike - and imports it INSIDE the function precisely so this
+# harness keeps working; its own comment says so. Nothing graded below calls
+# `optional_keys()`, so no mutant here is stubbed by that.
 def load(pairs):
     """`app/mqtt.py` with `pairs` applied, executed into a fresh module.