refactor: Convert AGVPathResult.Path from List<string> to List<MapNode>

## Summary
- Changed Path property type from List<string> to List<MapNode> for better type safety
- Eliminated O(n) node lookups throughout pathfinding system
- Added DirectionalHelper with motor direction consistency bonus/penalty
- Updated all path processing to work with MapNode objects directly

## Files Modified
- AGVPathResult.cs: Path property and CreateSuccess() method signature
- AStarPathfinder.cs: Path generation and node lookup optimization
- AGVPathfinder.cs: Path processing with MapNode objects
- DirectionChangePlanner.cs: Direction change planning with MapNode paths
- DockingValidator.cs: Docking validation with direct node access
- UnifiedAGVCanvas.Events.cs: Path visualization with MapNode iteration
- UnifiedAGVCanvas.cs: Destination node access
- VirtualAGV.cs: Path conversion to string IDs for storage
- DirectionalHelper.cs: Enhanced with motor direction awareness
- NodeMotorInfo.cs: Updated for new path structure

## Benefits
- Performance: Eliminated O(n) lookup searches
- Type Safety: Compile-time checking for node properties
- Code Quality: Direct property access instead of repeated lookups
- Maintainability: Single source of truth for node data

## Build Status
✅ AGVNavigationCore: Build successful (0 errors, 2 warnings)

🤖 Generated with Claude Code
Co-Authored-By: Claude <noreply@anthropic.com>

Cs_HMI/AGVLogic/AGVNavigationCore/Models/VirtualAGV.cs

@@ -272,7 +272,7 @@ namespace AGVNavigationCore.Models
             }
 
             _currentPath = path;
-            _remainingNodes = new List<string>(path.Path);
+            _remainingNodes = new List<string>(path.Path.Select(n => n.NodeId).ToList());
             _currentNodeIndex = 0;
 
             // 시작 노드와 목표 노드 설정