feat(epc): persist PV arrays and floor heat-loss flags

Add EPC persistence schema for two round-trip-fidelity gaps so the Model
backend can store the full EpcPropertyData faithfully:

- New child table epc_photovoltaic_array (one row per PV array), mirroring
  the epc_window child-table pattern.
- epc_floor_dimension: add is_exposed_floor and is_above_partially_heated_space
  boolean flags (NOT NULL DEFAULT false; additive, no backfill).

Includes generated migration 0245_magenta_nomad.sql + snapshot/journal.

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

src/app/db/migrations/0245_magenta_nomad.sql

@@ -0,0 +1,13 @@
+CREATE TABLE "epc_photovoltaic_array" (
+	"id" bigserial PRIMARY KEY NOT NULL,
+	"epc_property_id" bigint NOT NULL,
+	"array_index" integer NOT NULL,
+	"peak_power" real NOT NULL,
+	"pitch" integer NOT NULL,
+	"overshading" integer NOT NULL,
+	"orientation" integer
+);
+--> statement-breakpoint
+ALTER TABLE "epc_floor_dimension" ADD COLUMN "is_exposed_floor" boolean DEFAULT false NOT NULL;--> statement-breakpoint
+ALTER TABLE "epc_floor_dimension" ADD COLUMN "is_above_partially_heated_space" boolean DEFAULT false NOT NULL;--> statement-breakpoint
+ALTER TABLE "epc_photovoltaic_array" ADD CONSTRAINT "epc_photovoltaic_array_epc_property_id_epc_property_id_fk" FOREIGN KEY ("epc_property_id") REFERENCES "public"."epc_property"("id") ON DELETE no action ON UPDATE no action;

src/app/db/migrations/meta/_journal.json

@@ -1709,6 +1709,13 @@
       "when": 1782387040698,
       "tag": "0244_unknown_puck",
       "breakpoints": true
+    },
+    {
+      "idx": 245,
+      "version": "7",
+      "when": 1782491854452,
+      "tag": "0245_magenta_nomad",
+      "breakpoints": true
     }
   ]
 }

src/app/db/schema/property.ts

@@ -776,6 +776,8 @@ export const epcFloorDimension = pgTable(
     heatLossPerimeterM:   real("heat_loss_perimeter_m").notNull(),
     floorInsulation:      integer("floor_insulation"),
     floorConstruction:    integer("floor_construction"),
+    isExposedFloor:              boolean("is_exposed_floor").notNull().default(false),
+    isAbovePartiallyHeatedSpace: boolean("is_above_partially_heated_space").notNull().default(false),
   },
 );
 
@@ -810,6 +812,24 @@ export const epcWindow = pgTable(
   },
 );
 
+// ─── epc_photovoltaic_array ───────────────────────────────────────────────────
+
+export const epcPhotovoltaicArray = pgTable(
+  "epc_photovoltaic_array",
+  {
+    id:             bigserial("id", { mode: "bigint" }).primaryKey(),
+    epcPropertyId:  bigint("epc_property_id", { mode: "bigint" })
+      .notNull()
+      .references(() => epcProperty.id),
+
+    arrayIndex:   integer("array_index").notNull(), // preserves list order for round-trip equality
+    peakPower:    real("peak_power").notNull(),      // kWp, float (e.g. 3.24)
+    pitch:        integer("pitch").notNull(),        // SAP pitch CODE (categorical int, not degrees)
+    overshading:  integer("overshading").notNull(),  // SAP overshading CODE (categorical int)
+    orientation:  integer("orientation"),            // SAP orientation CODE, nullable
+  },
+);
+
 // ─── epc_energy_element ───────────────────────────────────────────────────────
 
 export const epcEnergyElement = pgTable(