feat(WEB): 절곡품 선생산→재고적재 Phase 1 - 생산입고 기반 구축

- StockTransaction: REASON_PRODUCTION_OUTPUT 상수 및 '생산입고' 라벨 추가
- StockLot: work_order_id FK 컬럼 마이그레이션 + 모델 fillable/casts/relation 추가
- StockService: increaseFromProduction() 메서드 구현 (increaseFromReceiving 기반)
- WorkOrderService: 완료 시 sales_order_id 유무에 따라 출하/재고입고 분기
  - stockInFromProduction(): 품목별 양품 재고 입고 처리
  - shouldStockIn(): items.options 기반 입고 대상 판단

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

app/Services/StockService.php

@@ -3,6 +3,8 @@
 namespace App\Services;
 
 use App\Models\Items\Item;
+use App\Models\Production\WorkOrder;
+use App\Models\Production\WorkOrderItem;
 use App\Models\Tenants\Receiving;
 use App\Models\Tenants\Stock;
 use App\Models\Tenants\StockLot;
@@ -313,6 +315,99 @@ public function increaseFromReceiving(Receiving $receiving): StockLot
         });
     }
 
+    /**
+     * 생산 완료 시 완성품 재고 입고
+     *
+     * increaseFromReceiving()을 기반으로 구현.
+     * 선생산(수주 없는 작업지시) 완료 시 양품을 재고로 적재.
+     *
+     * @param  WorkOrder  $workOrder  선생산 작업지시
+     * @param  WorkOrderItem  $woItem  작업지시 품목
+     * @param  float  $goodQty  양품 수량
+     * @param  string  $lotNo  LOT 번호
+     * @return StockLot 생성된 StockLot
+     */
+    public function increaseFromProduction(
+        WorkOrder $workOrder,
+        WorkOrderItem $woItem,
+        float $goodQty,
+        string $lotNo
+    ): StockLot {
+        if (! $woItem->item_id) {
+            throw new \Exception(__('error.stock.item_id_required'));
+        }
+
+        $tenantId = $this->tenantId();
+        $userId = $this->apiUserId();
+
+        return DB::transaction(function () use ($workOrder, $woItem, $goodQty, $lotNo, $tenantId, $userId) {
+            // 1. Stock 조회 또는 생성
+            $stock = $this->getOrCreateStock($woItem->item_id);
+
+            // 2. FIFO 순서 계산
+            $fifoOrder = $this->getNextFifoOrder($stock->id);
+
+            // 3. StockLot 생성
+            $stockLot = new StockLot;
+            $stockLot->tenant_id = $tenantId;
+            $stockLot->stock_id = $stock->id;
+            $stockLot->lot_no = $lotNo;
+            $stockLot->fifo_order = $fifoOrder;
+            $stockLot->receipt_date = now()->toDateString();
+            $stockLot->qty = $goodQty;
+            $stockLot->reserved_qty = 0;
+            $stockLot->available_qty = $goodQty;
+            $stockLot->unit = $woItem->unit ?? 'EA';
+            $stockLot->supplier = null;
+            $stockLot->supplier_lot = null;
+            $stockLot->po_number = null;
+            $stockLot->location = null;
+            $stockLot->status = 'available';
+            $stockLot->receiving_id = null;
+            $stockLot->work_order_id = $workOrder->id;
+            $stockLot->created_by = $userId;
+            $stockLot->updated_by = $userId;
+            $stockLot->save();
+
+            // 4. Stock 합계 갱신
+            $stock->refreshFromLots();
+
+            // 5. 거래 이력 기록
+            $this->recordTransaction(
+                stock: $stock,
+                type: StockTransaction::TYPE_IN,
+                qty: $goodQty,
+                reason: StockTransaction::REASON_PRODUCTION_OUTPUT,
+                referenceType: 'work_order',
+                referenceId: $workOrder->id,
+                lotNo: $lotNo,
+                stockLotId: $stockLot->id
+            );
+
+            // 6. 감사 로그 기록
+            $this->logStockChange(
+                stock: $stock,
+                action: 'production_in',
+                reason: 'production_output',
+                referenceType: 'work_order',
+                referenceId: $workOrder->id,
+                qtyChange: $goodQty,
+                lotNo: $lotNo
+            );
+
+            Log::info('Stock increased from production', [
+                'work_order_id' => $workOrder->id,
+                'item_id' => $woItem->item_id,
+                'stock_id' => $stock->id,
+                'stock_lot_id' => $stockLot->id,
+                'qty' => $goodQty,
+                'lot_no' => $lotNo,
+            ]);
+
+            return $stockLot;
+        });
+    }
+
     /**
      * 입고 수정 시 재고 조정 (차이만큼 증감)
      *