Add support for homekit air quality sensors (#30510)

* Add air quality sensor

* Fix comment from review

* Fix comment from review

* Lint fix

tests/components/homekit_controller/test_air_quality.py

@@ -0,0 +1,47 @@
+"""Basic checks for HomeKit air quality sensor."""
+from tests.components.homekit_controller.common import FakeService, setup_test_component
+
+
+def create_air_quality_sensor_service():
+    """Define temperature characteristics."""
+    service = FakeService("public.hap.service.sensor.air-quality")
+
+    cur_state = service.add_characteristic("air-quality")
+    cur_state.value = 5
+
+    cur_state = service.add_characteristic("density.ozone")
+    cur_state.value = 1111
+
+    cur_state = service.add_characteristic("density.no2")
+    cur_state.value = 2222
+
+    cur_state = service.add_characteristic("density.so2")
+    cur_state.value = 3333
+
+    cur_state = service.add_characteristic("density.pm25")
+    cur_state.value = 4444
+
+    cur_state = service.add_characteristic("density.pm10")
+    cur_state.value = 5555
+
+    cur_state = service.add_characteristic("density.voc")
+    cur_state.value = 6666
+
+    return service
+
+
+async def test_air_quality_sensor_read_state(hass, utcnow):
+    """Test reading the state of a HomeKit temperature sensor accessory."""
+    sensor = create_air_quality_sensor_service()
+    helper = await setup_test_component(hass, [sensor])
+
+    state = await helper.poll_and_get_state()
+    assert state.state == "4444"
+
+    assert state.attributes["air_quality_text"] == "poor"
+    assert state.attributes["ozone"] == 1111
+    assert state.attributes["nitrogen_dioxide"] == 2222
+    assert state.attributes["sulphur_dioxide"] == 3333
+    assert state.attributes["particulate_matter_2_5"] == 4444
+    assert state.attributes["particulate_matter_10"] == 5555
+    assert state.attributes["volatile_organic_compounds"] == 6666