manager: Add slot to manually (re)discover managed devices

src/calng/CalibrationManager.py

@@ -412,6 +412,14 @@ class CalibrationManager(DeviceClientBase, Device):
         self.state = State.CHANGING
         background(self._instantiate_pipeline())
 
+    @Slot(
+        displayedName='Discover managed devices',
+        description='',
+        allowedStates=[State.ACTIVE])
+    async def discoverManagedDevices(self):
+        self.state = State.CHANGING
+        background(self._discover_managed_devices())
+
     @Slot(
         displayedName='Apply managed values',
         description='Set all managed keys to the values currently active on '
@@ -543,6 +551,15 @@ class CalibrationManager(DeviceClientBase, Device):
         for device_id in devices:
             self._check_new_device(device_id, devices[device_id, 'classId'])
 
+    async def _discover_managed_devices(self):
+        self._daq_device_ids.clear()
+        self._domain_device_ids.clear()
+        self._correction_device_ids.clear()
+
+        await self._check_topology()
+
+        self.state = State.ACTIVE
+
     async def _get_shared_keys(self, device_ids, keys):
         """Find the most common property values on devices."""