Add core device, child and camera modules to smartcamera (#1193)

Co-authored-by: Teemu R. <tpr@iki.fi>

kasa/experimental/modules/childdevice.py

@@ -0,0 +1,23 @@
+"""Module for child devices."""
+
+from ...device_type import DeviceType
+from ..smartcameramodule import SmartCameraModule
+
+
+class ChildDevice(SmartCameraModule):
+    """Implementation for child devices."""
+
+    NAME = "childdevice"
+    QUERY_GETTER_NAME = "getChildDeviceList"
+    QUERY_MODULE_NAME = "childControl"
+
+    def query(self) -> dict:
+        """Query to execute during the update cycle.
+
+        Default implementation uses the raw query getter w/o parameters.
+        """
+        return {self.QUERY_GETTER_NAME: {self.QUERY_MODULE_NAME: {"start_index": 0}}}
+
+    async def _check_supported(self) -> bool:
+        """Additional check to see if the module is supported by the device."""
+        return self._device.device_type is DeviceType.Hub