Messaging agent

Not in this version. The way to talk to the inventory from a phone is the Android app: a photo of a label read and saved, and a voice note held to the item, kept as your words and read back. A messaging channel, where a photo sent to a business number comes back with the reading and a link to the item, would call the same API the web app and the phone call; no webhook, signature check or media download exists in the service. It stays under Next steps.