Add mop module (#1456)

Adds the following new features: a setting to control water level and a sensor if the mop is attached:
```
Mop water level (mop_waterlevel): *Disable* Low Medium High
Mop attached (mop_attached): True
```

tests/smart/modules/test_mop.py

@@ -0,0 +1,58 @@
+from __future__ import annotations
+
+import pytest
+from pytest_mock import MockerFixture
+
+from kasa import Module
+from kasa.smart import SmartDevice
+from kasa.smart.modules.mop import Waterlevel
+
+from ...device_fixtures import get_parent_and_child_modules, parametrize
+
+mop = parametrize("has mop", component_filter="mop", protocol_filter={"SMART"})
+
+
+@mop
+@pytest.mark.parametrize(
+    ("feature", "prop_name", "type"),
+    [
+        ("mop_attached", "mop_attached", bool),
+        ("mop_waterlevel", "waterlevel", str),
+    ],
+)
+async def test_features(dev: SmartDevice, feature: str, prop_name: str, type: type):
+    """Test that features are registered and work as expected."""
+    mod = next(get_parent_and_child_modules(dev, Module.Mop))
+    assert mod is not None
+
+    prop = getattr(mod, prop_name)
+    assert isinstance(prop, type)
+
+    feat = mod._device.features[feature]
+    assert feat.value == prop
+    assert isinstance(feat.value, type)
+
+
+@mop
+async def test_mop_waterlevel(dev: SmartDevice, mocker: MockerFixture):
+    """Test dust mode."""
+    mop_module = next(get_parent_and_child_modules(dev, Module.Mop))
+    call = mocker.spy(mop_module, "call")
+
+    waterlevel = mop_module._device.features["mop_waterlevel"]
+    assert mop_module.waterlevel == waterlevel.value
+
+    new_level = Waterlevel.High
+    await mop_module.set_waterlevel(new_level.name)
+
+    params = mop_module._settings.copy()
+    params["cistern"] = new_level.value
+
+    call.assert_called_with("setCleanAttr", params)
+
+    await dev.update()
+
+    assert mop_module.waterlevel == new_level.name
+
+    with pytest.raises(ValueError, match="Invalid waterlevel"):
+        await mop_module.set_waterlevel("invalid")