Deprecate Home Assistant entity attributes

[frenck]

This PR deprecates the use of Home Assistant entity attributes.

There are multiple reasons to deprecate support for this:

• Home Assistant has been actively reducing and rejecting the use of additional/separate states in the entity attributes.
• The entity attributes provided by the Home Assistant discovery in Zigbee2MQTT are duplicates of other entities.
• Attribute updates trigger updates in the Home Assistant state machine for the entity. E.g., the humidity attribute of a temperature entity changes... thus triggers a state update for the temperature entity. This is confusing and unneeded.
• Entity attributes are harder to use in Home Assistant automations. There is no need either, as they are already available as separate entities.
• All state changes are stored in the database, including their attributes (as it is part of the state). This means a lot of additional overhead is stored.

Additionally, it helps to provide a better experience with Zigbee2MQTT out of the box.

An advanced configuration parameter is provided to restore old behavior if needed.

advanced:
  homeassistant_legacy_entity_attributes: true

Before:

After:

(ignore the state in this screenshot, it's about the attributes column)

Documentation PR: Koenkk/zigbee2mqtt.io#780

[frenck]

Rebased PR onto the latest dev branch to catch up with changes. Adjusted the tests to match those latest changes and pass again.

[frenck]

Rebased PR onto the latest dev branch to catch up with changes.

[Koenkk]

Thanks! 😄

[andriej]

How about remote 'action' attributes on battery entities?
Currently it's the way to do automations based on button pressed in YAML (as device-trigger is UI only or needs separate automation per each button/action).

Will it stay?

[frenck]

That is not related to this change.

For your subject, you can find documentation here: https://www.zigbee2mqtt.io/integration/home_assistant.html#responding-to-button-clicks