feat:개소별 자재 투입 관리 API 추가

- work_order_material_inputs 테이블 신규 생성 (개소별 자재 투입 추적)
- 개소별 자재 조회/투입/이력/삭제/수정 API 5개 추가
- StockService.increaseToLot: LOT 수량 복원 메서드 추가
- WorkOrderService에 개소별 자재 투입 비즈니스 로직 구현
- WorkOrder, WorkOrderItem 모델에 materialInputs 관계 추가

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

app/Services/StockService.php

@@ -703,6 +703,90 @@ public function decreaseFromLot(int $stockLotId, float $qty, string $reason, int
         });
     }
 
+    /**
+     * 특정 LOT에 수량 복원 (투입 취소, 삭제 등)
+     * decreaseFromLot의 역방향
+     */
+    public function increaseToLot(int $stockLotId, float $qty, string $reason, int $referenceId): array
+    {
+        $tenantId = $this->tenantId();
+        $userId = $this->apiUserId();
+
+        return DB::transaction(function () use ($stockLotId, $qty, $reason, $referenceId, $tenantId, $userId) {
+            $lot = StockLot::where('tenant_id', $tenantId)
+                ->where('id', $stockLotId)
+                ->lockForUpdate()
+                ->first();
+
+            if (! $lot) {
+                throw new \Exception(__('error.stock.lot_not_available'));
+            }
+
+            $stock = Stock::where('id', $lot->stock_id)
+                ->lockForUpdate()
+                ->first();
+
+            if (! $stock) {
+                throw new \Exception(__('error.stock.not_found'));
+            }
+
+            $oldStockQty = $stock->stock_qty;
+
+            // LOT 수량 복원
+            $lot->qty += $qty;
+            $lot->available_qty += $qty;
+            $lot->updated_by = $userId;
+
+            if ($lot->status === 'used' && $lot->qty > 0) {
+                $lot->status = 'available';
+            }
+            $lot->save();
+
+            // Stock 정보 갱신
+            $stock->refreshFromLots();
+
+            // 거래 이력 기록
+            $this->recordTransaction(
+                stock: $stock,
+                type: StockTransaction::TYPE_IN,
+                qty: $qty,
+                reason: $reason,
+                referenceType: $reason,
+                referenceId: $referenceId,
+                lotNo: $lot->lot_no,
+                stockLotId: $lot->id
+            );
+
+            // 감사 로그
+            $this->logStockChange(
+                stock: $stock,
+                action: 'stock_increase',
+                reason: $reason,
+                referenceType: $reason,
+                referenceId: $referenceId,
+                qtyChange: $qty,
+                lotNo: $lot->lot_no
+            );
+
+            Log::info('Stock increased to specific lot', [
+                'stock_lot_id' => $stockLotId,
+                'lot_no' => $lot->lot_no,
+                'qty' => $qty,
+                'reason' => $reason,
+                'reference_id' => $referenceId,
+                'old_stock_qty' => $oldStockQty,
+                'new_stock_qty' => $stock->stock_qty,
+            ]);
+
+            return [
+                'lot_id' => $lot->id,
+                'lot_no' => $lot->lot_no,
+                'restored_qty' => $qty,
+                'remaining_qty' => $lot->qty,
+            ];
+        });
+    }
+
     /**
      * 품목별 가용 재고 조회
      *