A normalized inbound Zigbee APS message.
Every Zigbee.Adapter backend emits these as {:zigbee, :message, %Zigbee.Message{}}
regardless of the underlying radio/NCP, so the application layer (Zigbee.Interview,
Zigbee.ZCL, Zigbee.ZDO) never sees chip-specific frame formats. The payload
is the raw APS payload (a ZCL frame on an application profile, or a ZDO frame on
profile 0x0000), decoded by Zigbee.ZCL / Zigbee.ZDO.