refactor: unify date handling with utility functions

- Replaced direct date manipulations with utility functions like `getToday`, `parseDate`, and `createDateFromParts` across various components and services for consistency.
- Updated date initialization in `JiraAnalyticsService`, `BackupService`, and `DailyClient` to improve clarity and maintainability.
- Enhanced date parsing in forms and API routes to ensure proper handling of date strings.

src/lib/backup-utils.ts

@@ -3,7 +3,7 @@ import { exec } from 'child_process';
 import { promisify } from 'util';
 import path from 'path';
 import { createHash } from 'crypto';
-import { formatDateForDisplay, getToday } from './date-utils';
+import { formatDateForDisplay, getToday, parseDate } from './date-utils';
 
 const execAsync = promisify(exec);
 
@@ -160,7 +160,7 @@ export class BackupUtils {
       // Format: 2025-09-18T14-12-05-737Z -> 2025-09-18T14:12:05.737Z
       const isoString = dateMatch[2]
         .replace(/T(\d{2})-(\d{2})-(\d{2})-(\d{3})Z/, 'T$1:$2:$3.$4Z');
-      date = new Date(isoString);
+      date = parseDate(isoString);
     }
     
     return { type, date };
@@ -170,7 +170,7 @@ export class BackupUtils {
    * Génère un nom de fichier de backup
    */
   static generateBackupFilename(type: 'manual' | 'automatic'): string {
-    const timestamp = new Date().toISOString().replace(/[:.]/g, '-');
+    const timestamp = getToday().toISOString().replace(/[:.]/g, '-');
     return `towercontrol_${type}_${timestamp}.db`;
   }