Keep printer-agent progress in sync

Keep the shared task progress aligned with agent
reports that lack Bambu cloud task identity.

Release the lazily allocated task during reset to
avoid leaks when machine objects reconnect.

src/slic3r/GUI/DeviceManager.hpp

@@ -894,6 +894,7 @@ public:
     static bool is_in_printing_status(std::string status);
 
     void set_print_state(std::string status);
+    void update_print_progress(const json& value);
 
     bool is_connected();
     bool is_connecting();