✨ Enhanced mindmap visualization with professional UI

🎯 Major Features Added:
- Snap to grid functionality (20x20 grid, default enabled)
- Tidy Up button for instant node reorganization
- Copy node values with one-click clipboard integration
- HTML rendering toggle (render/raw modes for HTML content)
- Accordion-style collapsible panels (Controls & Legend)
- Automatic fitView on fullscreen toggle with smooth animations

🎨 UI/UX Improvements:
- Professional accordion layout with exclusive panel opening
- Consistent button alignment and styling across all controls
- Legend moved to top-right with icon+color indicators
- Vertical button stack: Controls → Legend → Tidy Up → Fullscreen
- Smooth transitions and hover effects throughout
- Clean, uncluttered interface with folded panels by default

🔧 Technical Enhancements:
- Fixed ResizeObserver errors with proper error handling
- Optimized React rendering with memo and useCallback
- Debounced DOM updates to prevent infinite loops
- React Flow instance management for programmatic control
- Removed redundant Raw Input button for cleaner interface

🚀 Performance & Stability:
- Error boundary implementation for ResizeObserver issues
- Proper cleanup of event listeners and timeouts
- Memoized components to prevent unnecessary re-renders
- Smooth 300ms animations for all state transitions

package.json

@@ -26,6 +26,7 @@
     "react-dom": "18.3.1",
     "react-router-dom": "6.26.2",
     "react-scripts": "5.0.1",
+    "reactflow": "^11.11.4",
     "serialize-javascript": "^6.0.0",
     "web-vitals": "^2.1.4"
   },