feat(08-02): create 5 dashboard chart components with ChartSection container

- Add RunActivityChart (area chart), SuccessRateChart (line chart), CostTrendChart (area chart), AgentWorkloadChart (bar chart) using Recharts
- Add BudgetUtilization with CSS progress bars, color thresholds (success/warn/danger), and empty state
- Create ChartSection container orchestrating all charts with Framer Motion entrance animation
- Integrate ChartSection into Dashboard.tsx between MetricsGrid and NeedsAttention
- Add companyId prop to DashboardProps and pass from App.tsx
- Include Plan 01 infrastructure: chart-utils.ts, ChartCard.tsx, ChartTooltip.tsx, recharts dependency
- All charts respect reduced motion via useReducedMotion hook
- 16 unit tests pass for aggregation functions

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

package.json

@@ -47,6 +47,7 @@
     "immer": "^11.1.4",
     "react": "19.2.4",
     "react-dom": "19.2.4",
+    "recharts": "^3.8.1",
     "tailwind-merge": "3.5.0",
     "zod": "4.3.6",
     "zustand": "^5.0.12"