Add Recharts bar charts to Today dashboard summary.

Extend the Today summary API with treatment mix and workflow task breakdowns, and render permission-aware chart cards on the Today page using Recharts.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/types/today.ts

@@ -1,3 +1,14 @@
+export type TodayChartBucket = {
+  code: string;
+  label: string;
+  count: number;
+};
+
+export type TodaySummaryCharts = {
+  treatmentMixWeek?: TodayChartBucket[];
+  tasksByWorkflowStep?: TodayChartBucket[];
+};
+
 export type TodayWidgetKey =
   | 'appointmentsToday'
   | 'patientsToday'
@@ -24,6 +35,7 @@ export interface TodaySummaryData {
   orgType: 'CLINIC' | 'LAB';
   range: { from: string; to: string };
   widgets: TodaySummaryWidgets;
+  charts: TodaySummaryCharts;
 }
 
 export interface TodaySummaryResponse {