feat(analytics): refactor model color management and fix UI display issues

- Extract getModelColor utility to lib/utils.ts with improved FNV-1a hash algorithm
- Replace hardcoded color palette with vibrant tones palette
- Remove color constants from model-breakdown-chart.tsx
- Fix truncated model names in analytics display
- Update project roadmap with analytics enhancements

docs/project-roadmap.md

@@ -589,6 +589,7 @@ src/types/
 **Release Date**: 2025-12-08
 
 #### UI Fixes & Improvements
+- ✅ **Analytics UI Enhancements**: Standardized colors, fixed truncated model names, and ensured color consistency in the analytics dashboard.
 - ✅ **Auto-formatting**: 31 UI files auto-formatted for consistent styling.
 - ✅ **Fast Refresh Exports**: Resolved `react-refresh/only-export-components` by extracting `buttonVariants`, `useSidebar`, and `useWebSocketContext` to separate files.
 - ✅ **React Hooks Issues**: Fixed `react-hooks/purity` (`Math.random()` in `useMemo` for `sidebar.tsx`) and `react-hooks/set-state-in-effect` (`use-theme.ts`, `settings.tsx`).
@@ -821,6 +822,6 @@ src/types/
 ---
 
 **Document Status**: Living document, updated with each major release
-**Last Updated**: 2025-12-08 (UI Layout Improvements)
+**Last Updated**: 2025-12-09 (Analytics UI Enhancements)
 **Next Update**: v4.6.0 UI Enhancements Planning
 **Maintainer**: CCS Development Team