Map built_form on full-SAP certs 🟩

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

datatypes/epc/domain/mapper.py

@@ -745,6 +745,9 @@ class EpcPropertyDataMapper:
                 if schema.property_type is not None
                 else None
             ),
+            built_form=(
+                str(schema.built_form) if schema.built_form is not None else None
+            ),
             dwelling_type=(
                 schema.dwelling_type
                 if isinstance(schema.dwelling_type, str)

datatypes/epc/schema/sap_schema_17_1.py

@@ -206,6 +206,9 @@ class SapSchema17_1:
     # home). Feeds the calculator's house/flat heat-transmission split; left
     # absent the dwelling is classified as neither → mis-scored (ADR-0037).
     property_type: Optional[int] = None
+    # gov built_form code (1 detached … 6 enclosed mid-terrace). Carried for the
+    # property-details panel and exposed-side handling (ADR-0037).
+    built_form: Optional[int] = None
     # measured living-room area (m²); the engine consumes it via a back-solved
     # habitable_rooms_count (Table 27). Optional — 100% present in the corpus.
     living_area: Optional[Union[int, float]] = None