feat: livrer ticket #93 et finaliser #17 avec gestion des Relais (#95)

Homogénéise le dashboard admin (onglets/listes/cartes/états) via composants réutilisables, finalise la création gestionnaire côté backend, et intègre la gestion des Relais avec rattachement gestionnaire.

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

frontend/lib/screens/administrateurs/admin_dashboardScreen.dart

@@ -1,10 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:p_tits_pas/services/configuration_service.dart';
-import 'package:p_tits_pas/widgets/admin/assistante_maternelle_management_widget.dart';
-import 'package:p_tits_pas/widgets/admin/gestionnaire_management_widget.dart';
-import 'package:p_tits_pas/widgets/admin/parent_managmant_widget.dart';
-import 'package:p_tits_pas/widgets/admin/admin_management_widget.dart';
 import 'package:p_tits_pas/widgets/admin/parametres_panel.dart';
+import 'package:p_tits_pas/widgets/admin/user_management_panel.dart';
 import 'package:p_tits_pas/widgets/app_footer.dart';
 import 'package:p_tits_pas/widgets/admin/dashboard_admin.dart';
 
@@ -18,7 +15,7 @@ class AdminDashboardScreen extends StatefulWidget {
 class _AdminDashboardScreenState extends State<AdminDashboardScreen> {
   bool? _setupCompleted;
   int mainTabIndex = 0;
-  int subIndex = 0;
+  int settingsSubIndex = 0;
 
   @override
   void initState() {
@@ -26,6 +23,11 @@ class _AdminDashboardScreenState extends State<AdminDashboardScreen> {
     _loadSetupStatus();
   }
 
+  @override
+  void dispose() {
+    super.dispose();
+  }
+
   Future<void> _loadSetupStatus() async {
     try {
       final completed = await ConfigurationService.getSetupStatus();
@@ -35,10 +37,12 @@ class _AdminDashboardScreenState extends State<AdminDashboardScreen> {
         if (!completed) mainTabIndex = 1;
       });
     } catch (e) {
-      if (mounted) setState(() {
-        _setupCompleted = false;
-        mainTabIndex = 1;
-      });
+      if (mounted) {
+        setState(() {
+          _setupCompleted = false;
+          mainTabIndex = 1;
+        });
+      }
     }
   }
 
@@ -48,9 +52,9 @@ class _AdminDashboardScreenState extends State<AdminDashboardScreen> {
     });
   }
 
-  void onSubTabChange(int index) {
+  void onSettingsSubTabChange(int index) {
     setState(() {
-      subIndex = index;
+      settingsSubIndex = index;
     });
   }
 
@@ -80,9 +84,11 @@ class _AdminDashboardScreenState extends State<AdminDashboardScreen> {
       body: Column(
         children: [
           if (mainTabIndex == 0)
-            DashboardUserManagementSubBar(
-              selectedSubIndex: subIndex,
-              onSubTabChange: onSubTabChange,
+            const SizedBox.shrink()
+          else
+            DashboardSettingsSubBar(
+              selectedSubIndex: settingsSubIndex,
+              onSubTabChange: onSettingsSubTabChange,
             ),
           Expanded(
             child: _getBody(),
@@ -95,19 +101,11 @@ class _AdminDashboardScreenState extends State<AdminDashboardScreen> {
 
   Widget _getBody() {
     if (mainTabIndex == 1) {
-      return ParametresPanel(redirectToLoginAfterSave: !_setupCompleted!);
-    }
-    switch (subIndex) {
-      case 0:
-        return const GestionnaireManagementWidget();
-      case 1:
-        return const ParentManagementWidget();
-      case 2:
-        return const AssistanteMaternelleManagementWidget();
-      case 3:
-        return const AdminManagementWidget();
-      default:
-        return const Center(child: Text('Page non trouvée'));
+      return ParametresPanel(
+        redirectToLoginAfterSave: !_setupCompleted!,
+        selectedSettingsTabIndex: settingsSubIndex,
+      );
     }
+    return const AdminUserManagementPanel();
   }
 }