Adds the user-simulated 001431 case (the cert that drove S0380.189/.190)
as an Elmhurst-only e2e fixture: Summary PDF → extractor → mapper →
calculator, every Block-1 SapResult field pinned against the
P960-0001-001431 worksheet at abs=1e-4. All 11 pins pass with zero
residual — the case is clean, confirming the S0380.190 gas-combi fuel
derivation closes the Summary path natively.
Verified the handover's flagged "+0.0007 SAP" was a target artifact, not
a cascade gap: the worksheet displays ECF (257) rounded to 1.6047 and
integer SAP (258)=78; the cascade's continuous SAP is computed from the
UNROUNDED ECF = (255)*(256)/((4)+45) = 660.9750*0.4200/173.0, giving
77.6147 — which matches the worksheet's own unrounded value. Pinning the
continuous SAP from the display-rounded ECF (→ 77.6144) was the wrong
target. Block-1 line refs all match exactly: (211) 10699.7225, (219)
3327.1592, (231) 86.0, (232) 283.2229, (255) 660.9750, (272) 3000.1664,
Σ(98) 8987.7669.
Summary mirrored into the tracked fixtures dir as
Summary_001431_gas_combi.pdf (distinct name — the corpus reuses cert
001431 across every heating variant); source Summary + worksheet tracked
under sap worksheets/golden fixture debugging/ as the pin ground truth.
2302 passed (+11), 0 failed; pyright net-zero on new/changed files.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>