refactor: enhance date handling across components

- Replaced direct date manipulations with utility functions for consistency and readability.
- Updated date formatting in `DailyCalendar`, `RecentTasks`, `CompletionRateChart`, and other components to use `formatDateShort` and `formatDateForDisplay`.
- Improved date parsing in `JiraLogs`, `JiraSchedulerConfig`, and `BackupSettingsPageClient` to ensure proper handling of date strings.
- Streamlined date initialization in `useDaily` and `DailyService` to utilize `getToday` and `getYesterday` for better clarity.

src/components/dashboard/charts/CompletionRateChart.tsx

@@ -2,6 +2,7 @@
 
 import { LineChart, Line, XAxis, YAxis, CartesianGrid, Tooltip, ResponsiveContainer } from 'recharts';
 import { DailyMetrics } from '@/services/metrics';
+import { parseDate, formatDateShort } from '@/lib/date-utils';
 
 interface CompletionRateChartProps {
   data: DailyMetrics[];
@@ -12,7 +13,7 @@ export function CompletionRateChart({ data, className }: CompletionRateChartProp
   // Transformer les données pour le graphique
   const chartData = data.map(day => ({
     day: day.dayName.substring(0, 3), // Lun, Mar, etc.
-    date: new Date(day.date).toLocaleDateString('fr-FR', { day: '2-digit', month: '2-digit' }),
+    date: formatDateShort(parseDate(day.date)),
     completionRate: day.completionRate,
     completed: day.completed,
     total: day.totalTasks