Add MQTT notify platform (#64728)

* Mqtt Notify service draft

* fix updates

* Remove TARGET config parameter

* do not use protected attributes

* complete tests

* device support for auto discovery

* Add targets attribute and support for data param

* Add tests and resolve naming issues

* CONF_COMMAND_TEMPLATE from .const

* Use mqtt as default service name

* make sure service  has a unique name

* pylint error

* fix type error

* Conditional device removal and test

* Improve tests

* update description has_notify_services()

* Use TypedDict for service config

* casting- fix discovery - hass.data

* cleanup

* move MqttNotificationConfig after the schemas

* fix has_notify_services

* do not test log for reg update

* Improve casting types

* Simplify obtaining the device_id

Co-authored-by: Erik Montnemery <erik@montnemery.com>

* await not needed

Co-authored-by: Erik Montnemery <erik@montnemery.com>

* Improve casting types and naming

* cleanup_device_registry signature change and black

* remove not needed condition

Co-authored-by: Erik Montnemery <erik@montnemery.com>