So when events happen in Front (like an inbound message which might reopen a conversation), they typically contain just the context of what is happening now, and the current state of the conversation. If you need the previous state of the conversation (like if it was previously archived) you’ll need to fetch that additional data.

I’d probably recommend building this out as an Application Webhook. You would create a webhook subscription for the customer to listen for inbound message events, archives and reopens. 
On your side, keep a map of the conversation and it’s current known status (you can always call the GET /conversations/:id endpoint to check the status if necessary.
On inbound messages, determine if this is something that your app should react to, and have it handle the conversation accordingly. 

I hope that gives you some inspiration for a starting point - looking forward to seeing what you build!