fix: 견적→수주 변환 시 담당자 정보 누락 수정

- Order::createFromQuote() 잘못된 필드명 수정 (contact_person→contact, delivery_date→completion_date)
- 견적 담당자(manager)를 orders.options.manager_name에 저장
- StoreOrderRequest/UpdateOrderRequest에 options.manager_name 유효성 검증 추가
- WorkOrderService show()에서 salesOrder.options 컬럼 포함하여 담당자 표시

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Models/Orders/Order.php

@@ -325,15 +325,17 @@ public static function createFromQuote(Quote $quote, string $orderNo): self
             'status_code' => self::STATUS_DRAFT,
             'client_id' => $quote->client_id,
             'client_name' => $quote->client?->name,
-            'client_contact' => $quote->contact_person,
+            'client_contact' => $quote->contact,
             'site_name' => $quote->site_name,
             'quantity' => $quote->items->sum('calculated_quantity'),
             'supply_amount' => $quote->total_amount,
             'tax_amount' => round($quote->total_amount * 0.1, 2),
             'total_amount' => round($quote->total_amount * 1.1, 2),
-            'delivery_date' => $quote->delivery_date,
+            'delivery_date' => $quote->completion_date,
             'memo' => $quote->remarks,
-            'remarks' => $quote->internal_notes,
+            'options' => [
+                'manager_name' => $quote->manager,
+            ],
         ]);
     }
 }