Some context:
The Devices system has always been slightly confusing to me. Everything is fine when a device and all its entities are from a single integration. However, sometimes entities from other integrations are attached to a device that already exists. (E.g. a device tracker from my WiFi AP attaches to the Samsung TV device.) Perhaps this uses MAC addresses to match the devices? It is a very nice feature to have, but it doesn’t work 100% of the time. This results in duplicate devices or “orphan” entities that should be attached to a device.
Since entities aren’t always correctly assigned to their device, it would be nice if you could manually do this. The option to do this should probably go in the Advanced section of the entity settings.
It would also be useful to merge devices, but this could be a bit more complicated (e.g. picking a Manufacturer/Model value).
Sticking with the Samsung TV example, I would like to merge the device provided by the DLNA integration with the device provided by the Samsung TV integration. I would also like to assign a History Stats sensor (Daily TV Usage) to that device.
