Detect 1:1 conversations started on WhatsApp or Instagram

I'd like SAGA to recognise when I actually start a conversation with a contact on WhatsApp or Instagram — a direct message, not a broadcast — and reflect that on the contact, ideally using it as a trigger to move their card forward.

Right now WhatsApp in SAGA is for broadcasts and Instagram isn't a messaging channel at all, so a contact's stage can't update when I message them from my phone.