Add notify entity component (#110950)

* Add notify entity component

* Device classes, restore state, icons

* Add icons file

* Add tests for kitchen_sink

* Remove notify from no_entity_platforms in hassfest icons, translation link

* ruff

* Remove `data` feature

* Only message support

* Complete initial device classes

* mypy pylint

* Remove device_class implementation

* format

* Follow up comments

* Remove _attr_supported_features

* Use setup_test_component_platform

* User helper at other places

* last comment

* Add entry unload test and non async test

* Avoid default mutable object in constructor