Implement a system for dead letter queue consumption

[yakkomajuri]

We need to have a way to consume from the dead letter queue while maximizing for correctness after a full outage.

Changes required:

• [ ] Implement a mechanism to pipe dead letter queue events back through the /capture endpoint
• [ ] Implement a mechanism for determining when we’ve had a full outage and should prioritize dead letter queue events over new events
• [ ] Implement a configurable consumer from the dead letter queue