feat(features): refontes adhesions/admin/auth/backup/contributions/dashboard/epargne/events

- adhesions : bloc complet avec events/states/model, dialogs paiement/rejet
- admin : users bloc, user management list/detail pages
- authentication : bloc + keycloak auth service + webview
- backup : bloc complet, repository, models
- contributions : bloc + widgets + export
- dashboard : widgets connectés (activities, events, notifications, search)
  + charts + monitoring + shortcuts
- epargne : repository, transactions, dialogs
- events : bloc complet, pages (detail, connected, wrapper), models

lib/features/dashboard/presentation/widgets/metrics/real_time_metrics_widget.dart

@@ -86,7 +86,7 @@ class _RealTimeMetricsWidgetState extends State<RealTimeMetricsWidget>
         gradient: LinearGradient(
           begin: Alignment.topLeft,
           end: Alignment.bottomRight,
-          colors: [AppColors.brandGreen, AppColors.primaryGreen],
+          colors: [AppColors.primaryDark, AppColors.primary],
         ),
         borderRadius: BorderRadius.circular(10),
       ),