refactor(widgets): drop teardown dispatcher disconnects now handled by disconnect_owner

bec_widgets/widgets/plots/image/image.py

@@ -1068,8 +1068,7 @@ class Image(ImageBase):
         except Exception:  # noqa: BLE001
             pass
 
-        self.bec_dispatcher.disconnect_slot(self.on_scan_status, MessageEndpoints.scan_status())
-        self.bec_dispatcher.disconnect_slot(self.on_scan_progress, MessageEndpoints.scan_progress())
+        # Dispatcher slots are released by BECWidget.cleanup via disconnect_owner.
         super().cleanup()
 
 

bec_widgets/widgets/plots/scatter_waveform/scatter_waveform.py

@@ -740,8 +740,7 @@ class ScatterWaveform(PlotBase):
             self.scatter_dialog.deleteLater()
         if self.scatter_curve_settings is not None:
             self.scatter_curve_settings.cleanup()
-        self.bec_dispatcher.disconnect_slot(self.on_scan_status, MessageEndpoints.scan_status())
-        self.bec_dispatcher.disconnect_slot(self.on_scan_progress, MessageEndpoints.scan_progress())
+        # Dispatcher slots are released by BECWidget.cleanup via disconnect_owner.
         self.plot_item.removeItem(self._main_curve)
         self._main_curve = None
         super().cleanup()

bec_widgets/widgets/progress/ring_progress_bar/ring.py

@@ -639,11 +639,10 @@ class Ring(BECWidget, QWidget):
     def cleanup(self):
         """
         Cleanup the ring widget.
-        Disconnect any registered slots.
         """
-        if self.registered_slot is not None:
-            self.bec_dispatcher.disconnect_slot(*self.registered_slot)
-            self.registered_slot = None
+        # Dispatcher slots are released by BECWidget.cleanup via disconnect_owner;
+        # no per-widget disconnect is needed at teardown.
+        self.registered_slot = None
         self.progress_tracker.cleanup()
         self._hover_animation.stop()
         super().cleanup()