Change oav parameters direction attribute to enum from int (#2092)

Author: rtuck99

src/dodal/devices/oav/oav_parameters.py

@@ -7,6 +7,8 @@
 from daq_config_server import ConfigClient
 from daq_config_server.models import DisplayConfig
 
+from dodal.devices.oav.pin_image_recognition import ScanDirections
+
 # GDA currently assumes this aspect ratio for the OAV window size.
 # For some beamline this doesn't affect anything as the actual OAV aspect ratio
 # matches. Others need to take it into account to rescale the values stored in
@@ -99,7 +101,9 @@ def update(name, param_type, default=None):
         self.open_ksize: int = update("open_ksize", int, default=0)
         self.close_ksize: int = update("close_ksize", int, default=5)
         self.min_callback_time: float = update("min_callback_time", float, default=0.08)
-        self.direction: int = update("direction", int)
+        self.direction: ScanDirections = [*ScanDirections][
+            self.active_params["direction"]
+        ]
         self.max_tip_distance: float = update("max_tip_distance", float, default=300)
 
     def get_max_tip_distance_in_pixels(self, microns_per_pixel: float) -> float: