tots els singletons tornats a fer a la vieja y gorda usanza

source/service_menu.h

@@ -6,15 +6,10 @@
 class ServiceMenu
 {
 public:
-    static ServiceMenu &get_instance()
-    {
-        static ServiceMenu instance;
-        return instance;
-    }
-
-    // Eliminar copia y asignación
-    ServiceMenu(const ServiceMenu &) = delete;
-    ServiceMenu &operator=(const ServiceMenu &) = delete;
+    // --- Métodos de singleton ---
+    static void init();        // Inicializa el objeto ServiceMenu
+    static void destroy();     // Libera el objeto ServiceMenu
+    static ServiceMenu *get(); // Obtiene el puntero al objeto ServiceMenu
 
     void show();
     void render();
@@ -22,9 +17,16 @@ public:
     void execute_option(size_t option);
 
 private:
-    ServiceMenu();
-    ~ServiceMenu() = default;
+    // --- Patrón Singleton ---
+    ServiceMenu();                                        // Constructor privado
+    ~ServiceMenu() = default;                             // Destructor privado
+    ServiceMenu(const ServiceMenu &) = delete;            // Evitar copia
+    ServiceMenu &operator=(const ServiceMenu &) = delete; // Evitar asignación
 
+    // --- Singleton ---
+    static ServiceMenu *instance_;
+
+    // -- Variables internas ---
     bool is_active;
     size_t selected_option;
     std::vector<std::string> options;