refactor(ddg): add user access method to ddg

csaxs_bec/devices/epics/delay_generator_csaxs/ddg_1.py

@@ -133,7 +133,7 @@ class DDG1(PSIDeviceBase, DelayGeneratorCSAXS):
         device_manager (DeviceManagerBase | None, optional): Device manager. Defaults to None.
     """
 
-    USER_ACCESS = ["keep_shutter_open_during_scan", "set_trigger"]
+    USER_ACCESS = ["keep_shutter_open_during_scan", "set_trigger", "get_shutter_to_open_delay"]
 
     # TODO Consider using the 'fsh' device instead.
     fast_shutter_readback = Cpt(
@@ -231,6 +231,10 @@ class DDG1(PSIDeviceBase, DelayGeneratorCSAXS):
         self.burst_mode.put(0)
         time.sleep(0.02)
 
+    def get_shutter_to_open_delay(self) -> float:
+        """Get the current delay that is set to open the shutter before the exposure time."""
+        return self._shutter_to_open_delay
+
     def keep_shutter_open_during_scan(self, open: True) -> None:
         """
         Method to configure the delay generator for keeping the shutter open during a scans.