feat(production): 優化生產單 BOM 原物料選取邏輯，支援商品 -> 倉庫 -> 批號連動與 API 分佈查詢

app/Modules/Production/Controllers/ProductionOrderController.php

@@ -269,6 +269,33 @@ class ProductionOrderController extends Controller
         return response()->json($data);
     }
 
+    /**
+     * 取得商品在各倉庫的庫存分佈
+     */
+    public function getProductWarehouses($productId)
+    {
+        $inventories = \App\Modules\Inventory\Models\Inventory::with(['warehouse', 'product.baseUnit'])
+            ->where('product_id', $productId)
+            ->where('quantity', '>', 0)
+            ->get();
+            
+        $data = $inventories->map(function ($inv) {
+            return [
+                'id' => $inv->id, // Inventory ID
+                'warehouse_id' => $inv->warehouse_id,
+                'warehouse_name' => $inv->warehouse->name ?? '未知倉庫',
+                'batch_number' => $inv->batch_number,
+                'quantity' => $inv->quantity,
+                'expiry_date' => $inv->expiry_date ? $inv->expiry_date->format('Y-m-d') : null,
+                'unit_name' => $inv->product->baseUnit->name ?? '',
+                'base_unit_id' => $inv->product->base_unit_id ?? null,
+                'conversion_rate' => $inv->product->conversion_rate ?? 1,
+            ];
+        });
+
+        return response()->json($data);
+    }
+
     /**
      * 編輯生產單
      */