Add device class to ESPHome switches (#64919)

Co-authored-by: Jesse Hills <3060199+jesserockz@users.noreply.github.com>

homeassistant/components/esphome/switch.py

@@ -5,7 +5,7 @@ from typing import Any
 
 from aioesphomeapi import SwitchInfo, SwitchState
 
-from homeassistant.components.switch import SwitchEntity
+from homeassistant.components.switch import DEVICE_CLASSES, SwitchEntity
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
@@ -45,6 +45,13 @@ class EsphomeSwitch(EsphomeEntity[SwitchInfo, SwitchState], SwitchEntity):
         """Return true if the switch is on."""
         return self._state.state
 
+    @property
+    def device_class(self) -> str | None:
+        """Return the class of this device."""
+        if self._static_info.device_class not in DEVICE_CLASSES:
+            return None
+        return self._static_info.device_class
+
     async def async_turn_on(self, **kwargs: Any) -> None:
         """Turn the entity on."""
         await self._client.switch_command(self._static_info.key, True)