Area units and conversion between metric and US (#123563)

* area conversions

* start work on tests

* add number device class

* update unit conversions to utilise distance constants

* add area unit

* update test unit system

* update device condition and trigger

* update statistic unit converters

* further tests work WIP

* update test unit system

* add missing string translations

* fix websocket tests

* add deprecated notice

* add more missing strings and missing initialisation of unit system

* adjust icon and remove strings from scrape and random

* Fix acre to meters conversion

Co-authored-by: epenet <6771947+epenet@users.noreply.github.com>

* Tidy up valid units

Co-authored-by: epenet <6771947+epenet@users.noreply.github.com>

* fix ordering of area

* update order alphabetically

* fix broken test

* update test_init

* Update homeassistant/const.py

Co-authored-by: epenet <6771947+epenet@users.noreply.github.com>

* remove deprecated unit and fix alphabetical order

* change deprecation and add tests, change to millimeter conversion for inches

* fix order

* re-order defs alphabetically

* add measurement as well

* update icons

* fix up Deprecation of area square meters

* Update core integrations to UnitOfArea

* update test recorder tests

* unit system tests in alphabetical

* update snapshot

* rebuild

* revert alphabetization of functions

* other revert of alphabetical order

---------

Co-authored-by: epenet <6771947+epenet@users.noreply.github.com>

tests/components/sensor/test_init.py

@@ -30,6 +30,7 @@ from homeassistant.const import (
     PERCENTAGE,
     STATE_UNKNOWN,
     EntityCategory,
+    UnitOfArea,
     UnitOfDataRate,
     UnitOfEnergy,
     UnitOfLength,
@@ -651,6 +652,34 @@ async def test_custom_unit(
         "device_class",
     ),
     [
+        # Area
+        (
+            UnitOfArea.SQUARE_KILOMETERS,
+            UnitOfArea.SQUARE_MILES,
+            UnitOfArea.SQUARE_MILES,
+            1000,
+            "1000",
+            "386",
+            SensorDeviceClass.AREA,
+        ),
+        (
+            UnitOfArea.SQUARE_CENTIMETERS,
+            UnitOfArea.SQUARE_INCHES,
+            UnitOfArea.SQUARE_INCHES,
+            7.24,
+            "7.24",
+            "1.12",
+            SensorDeviceClass.AREA,
+        ),
+        (
+            UnitOfArea.SQUARE_KILOMETERS,
+            "peer_distance",
+            UnitOfArea.SQUARE_KILOMETERS,
+            1000,
+            "1000",
+            "1000",
+            SensorDeviceClass.AREA,
+        ),
         # Distance
         (
             UnitOfLength.KILOMETERS,
@@ -1834,6 +1863,7 @@ async def test_non_numeric_device_class_with_unit_of_measurement(
     [
         SensorDeviceClass.APPARENT_POWER,
         SensorDeviceClass.AQI,
+        SensorDeviceClass.AREA,
         SensorDeviceClass.ATMOSPHERIC_PRESSURE,
         SensorDeviceClass.BATTERY,
         SensorDeviceClass.CO,