docs: correct S0380.200 handover — interlock was already done; S0380.201 closed pumps

The flagged "priority" (per-main boiler interlock −5pp) was already
implemented (S0380.141 cylinder-thermostat path + S0380.177 room-
thermostat path); case 6 already produces (206)=79/(207)=84 exactly and
0240 is a combi with no cylinder. Records that S0380.201 closed the
secondary dual-system pump item and the remaining case-6 gaps (space
demand +1.28%, HW −1.6%) for full-SapResult promotion.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

domain/sap10_calculator/docs/HANDOVER_POST_S0380_200.md

@@ -30,7 +30,39 @@ Summaries mirrored to `backend/documents_parser/tests/fixtures/Summary_001431_ca
 
 ---
 
-## OPEN (the priority) — boiler-interlock −5pp efficiency adjustment, per main system
+## ⚠️ CORRECTION (post S0380.201) — the interlock priority was ALREADY DONE
+
+The "priority" below was **misdiagnosed**. At HEAD the cascade already
+produces case 6 (206) sys-1 eff = **79.0** and (207) sys-2 eff = **84.0**,
+matching the worksheet exactly. The cylinder-thermostat interlock path
+(`no_stored_hw_interlock = has_cylinder and cylinder_thermostat != "Y"`)
+has existed since **S0380.141**; the room-thermostat path since S0380.177.
+`no_interlock = no_room_thermostat OR no_stored_hw_interlock` — it does NOT
+only catch 2101/2102. Toggling case 6 `cylinder_thermostat` N→Y flips eff
+0.79→0.84, confirming the −5pp fires. Golden **0240 is a combi**
+(`has_hot_water_cylinder=False`) → correctly NOT penalised; its predicted
+re-pin from the interlock is void. The misread came from
+`energy_requirements_section_from_cert` (a §2.4 debug helper using raw
+`_main_heating_efficiency`, which reports 84 — the real `cert_to_inputs`
+cascade applies the −5pp at ~line 6071). See [[feedback-verify-handover-claims]].
+
+**S0380.201 landed the SECONDARY item** (dual-system aux pumps): SAP 10.2
+Table 4f note c) second main-system circulation pump, gated on a lodged
+`main_heating_fraction > 0`. Case 6 (231) 241 → **356** EXACT (= 41 Main-1
+pump + 115 Main-2 pump + 200 oil aux). 0240 re-pinned (pumps 315 → 430,
+integer 73 → 72, resid +0 → -1, PE +2.8092, CO2 +0.1385) — anticipated
+and authorised below. 000565 protected by the fraction>0 gate (its Main 2
+is a DHW-only combi, fraction 0).
+
+**Remaining case-6 gaps for full-SapResult promotion** (vs P960-0001-001431):
+- (98c) space demand cascade **12145.31** vs ws **11991.96** (+1.28%) —
+  living-area MIT (87) ~0.3 °C low in winter; multi-causal (gains/heat-loss).
+- (219) hot water cascade **4824.74** vs ws **4902.86** (−1.6%) — §4 walk needed.
+Once both close, promote case 6 to a full SapResult e2e fixture (pin grid below).
+
+---
+
+## OPEN (was the priority, now DONE) — boiler-interlock −5pp efficiency adjustment, per main system
 
 **Goal:** a RdSAP-10/SAP-10.2 **spec-accurate** implementation of the boiler
 interlock efficiency adjustment, applied **per main heating system**, done in