Enhance ListView pie charts with professional controls and improved layout

- Add zoom functionality with +/- controls and percentage display
- Implement individual Reset Layout buttons for each pie chart
- Redesign chart layout from grid to vertical stacking (one chart per row)
- Increase chart containers from 400px to 600px with 400px SVG content
- Change backgrounds from gray to black for better contrast
- Move chart titles outside containers for cleaner presentation
- Add comprehensive icon support for all chart legends
- Synchronize colors with filter dropdown options for consistency
- Implement smart legend layouts (2-line for Status/Priority, 3-per-row for Node Distribution)
- Add proper spacing between pie charts and legends
- Fix GraphContext mock data initialization fallback

Author: Patel230