Merge develop into master (squash)

- Ticket #92: endpoint GET /gestionnaires, dashboard admin données réelles
- Seed données de test, script reset-and-seed-db.sh
- Modèles frontend (Parent, AM), user_service, widgets admin

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

frontend/lib/services/api/api_config.dart

@@ -15,6 +15,9 @@ class ApiConfig {
   static const String users = '/users';
   static const String userProfile = '/users/profile';
   static const String userChildren = '/users/children';
+  static const String gestionnaires = '/gestionnaires';
+  static const String parents = '/parents';
+  static const String assistantesMaternelles = '/assistantes-maternelles';
 
   // Configuration (admin)
   static const String configuration = '/configuration';