Carry the Plan's post-works figures onto the export row 🟥

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

tests/domain/scenario_export/test_scenario_sheet.py

@@ -165,3 +165,29 @@ def test_solar_pv_with_a_battery_pivots_to_its_own_battery_column() -> None:
     assert row["solar_pv_with_battery"] == 6000.0
     assert row["solar_pv"] == ""
     assert row["total_retrofit_cost"] == 6000.0
+
+
+def test_plan_post_works_figures_come_from_the_plan_row_blank_when_absent() -> None:
+    # arrange — a Property whose default Plan carries the SAP calculator's
+    # post-works figures; the contingency figure happens to be absent.
+    prop = _property(
+        post_sap_points=78.0,
+        post_epc_rating="C",
+        cost_of_works=4200.0,
+        co2_savings=1.8,
+        energy_bill_savings=350.0,
+        energy_consumption_savings=4100.0,
+        valuation_increase=15000.0,
+    )
+
+    # act
+    sheet = shape_scenario_sheet([prop])
+
+    # assert — the persisted Plan figures pass through directly (no recompute,
+    # ADR-0065); an absent figure is blank rather than zero.
+    row = sheet.rows[0]
+    assert row["post_sap_points"] == 78.0
+    assert row["post_epc_rating"] == "C"
+    assert row["cost_of_works"] == 4200.0
+    assert row["valuation_increase"] == 15000.0
+    assert row["contingency_cost"] == ""