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/jira/SprintDetailModal.tsx

@@ -4,6 +4,7 @@ import { useState, useEffect, useCallback } from 'react';
 import { SprintVelocity, JiraTask, AssigneeDistribution, StatusDistribution } from '@/lib/types';
 import { Modal } from '@/components/ui/Modal';
 import { Card, CardHeader, CardContent } from '@/components/ui/Card';
+import { parseDate, formatDateForDisplay } from '@/lib/date-utils';
 import { Badge } from '@/components/ui/Badge';
 import { Button } from '@/components/ui/Button';
 
@@ -144,7 +145,7 @@ export default function SprintDetailModal({
             <div className="text-center">
               <div className="text-sm text-gray-600">Période</div>
               <div className="text-xs text-gray-500">
-                {new Date(sprint.startDate).toLocaleDateString('fr-FR')} - {new Date(sprint.endDate).toLocaleDateString('fr-FR')}
+                {formatDateForDisplay(parseDate(sprint.startDate))} - {formatDateForDisplay(parseDate(sprint.endDate))}
               </div>
             </div>
           </div>
@@ -318,7 +319,7 @@ export default function SprintDetailModal({
                           <div className="flex items-center gap-4 text-xs text-gray-500">
                             <span>📋 {issue.issuetype.name}</span>
                             <span>👤 {issue.assignee?.displayName || 'Non assigné'}</span>
-                            <span>📅 {new Date(issue.created).toLocaleDateString('fr-FR')}</span>
+                            <span>📅 {formatDateForDisplay(parseDate(issue.created))}</span>
                           </div>
                         </div>
                       </div>