[Feature request]: Auto-discovery for bridge/controller

[mundschenk-at]

Is your feature request related to a problem? Please describe

Currently, the ZigBee bridge/controller has to be added to Home Assistant manually (as described in https://www.zigbee2mqtt.io/guide/usage/integrations/home_assistant.html#controlling-zigbee2mqtt-via-home-assistant).

Describe the solution you'd like

The bridge device and relevant control & configuration entities should be auto-discovered. The capabilities of the MQTT integration have also expanded since the integration chapter was written, so I think some parts of it can now be covered without additional helper entities. The bridge device should be linked to the individual ZigBee devices using the via_device directive in the device object in the auto-discovery payload.

The scripts and automations could maybe converted to blueprints (allowing semi-automated installation) or left as a YAML file for the packages subfolder of the Home Assistant configuration.

Describe alternatives you've considered

Leaving things as is.

Additional context

None.

[mundschenk-at]

Fixed via #19994.