fix(mobile): URL changement mdp corrigée + v3.0 — multi-org, AppAuth, sécurité prod

Auth:
- profile_repository.dart: /api/auth/change-password → /api/membres/auth/change-password

Multi-org (Phase 3):
- OrgSelectorPage, OrgSwitcherBloc, OrgSwitcherEntry
- org_context_service.dart: headers X-Active-Organisation-Id + X-Active-Role

Navigation:
- MorePage: navigation conditionnelle par typeOrganisation
- Suppression adaptive_navigation (remplacé par main_navigation_layout)

Auth AppAuth:
- keycloak_webview_auth_service: fixes AppAuth Android
- AuthBloc: gestion REAUTH_REQUIS + premierLoginComplet

Onboarding:
- Nouveaux états: payment_method_page, onboarding_shared_widgets
- SouscriptionStatusModel mis à jour StatutValidationSouscription

Android:
- build.gradle: ProGuard/R8, network_security_config
- Gradle wrapper mis à jour

lib/core/navigation/main_navigation_layout.dart

@@ -31,6 +31,10 @@ class _MainNavigationLayoutState extends State<MainNavigationLayout> {
   String? _lastOrgId;
 
   Widget _getDashboardForRole(UserRole role, String userId, String? orgId) {
+    // Compte sans rôle métier — afficher la page d'attente sans appel API
+    if (role == UserRole.visitor) {
+      return const VisitorDashboard();
+    }
     if (role == UserRole.orgAdmin && (orgId == null || orgId.isEmpty)) {
       return OrgAdminDashboardLoader(userId: userId);
     }
@@ -83,8 +87,8 @@ class _MainNavigationLayoutState extends State<MainNavigationLayout> {
         MembersPageWrapper(
           organisationId: role == UserRole.orgAdmin ? orgId : null,
         ),
-      const EventsPageWrapper(),
-      const MorePage(),
+      if (role != UserRole.visitor) const EventsPageWrapper(),
+      if (role != UserRole.visitor) const MorePage(),
     ];
     return _cachedPages!;
   }
@@ -150,16 +154,18 @@ class _MainNavigationLayoutState extends State<MainNavigationLayout> {
           activeIcon: Icons.people_rounded,
           label: 'Membres',
         ),
-      const _NavItem(
-        icon: Icons.event_outlined,
-        activeIcon: Icons.event_rounded,
-        label: 'Événements',
-      ),
-      const _NavItem(
-        icon: Icons.more_horiz_rounded,
-        activeIcon: Icons.more_horiz_rounded,
-        label: 'Plus',
-      ),
+      if (role != UserRole.visitor) ...[
+        const _NavItem(
+          icon: Icons.event_outlined,
+          activeIcon: Icons.event_rounded,
+          label: 'Événements',
+        ),
+        const _NavItem(
+          icon: Icons.more_horiz_rounded,
+          activeIcon: Icons.more_horiz_rounded,
+          label: 'Plus',
+        ),
+      ],
     ];
   }
 }