Extract Collection helper from Person integration (#30313)

* Add CRUD foundation

* Use collection helper in person integration

* Lint/pytest

* Add tests

* Lint

* Create notification

homeassistant/components/websocket_api/const.py

@@ -3,9 +3,20 @@ import asyncio
 from concurrent import futures
 from functools import partial
 import json
+from typing import TYPE_CHECKING, Callable
 
+from homeassistant.core import HomeAssistant
 from homeassistant.helpers.json import JSONEncoder
 
+if TYPE_CHECKING:
+    from .connection import ActiveConnection  # noqa
+
+
+WebSocketCommandHandler = Callable[
+    [HomeAssistant, "ActiveConnection", dict], None
+]  # pylint: disable=invalid-name
+
+
 DOMAIN = "websocket_api"
 URL = "/api/websocket"
 MAX_PENDING_MSG = 512