Orchestrator processes only one segment at time

Nobody has claimed this yet.

**Describe the bug**
Orchestrator was made with assumption that segments coming in with realtime speed, in steady manner. That means, that orchestrator always have `segment length` seconds to process segment before next one arrives. But there are legitimate cases - see [here](#885 ) (and probably it can happen in real networks, with data buffer somewhere along the way and then arrived to broadcaster in big batch) - when this is not the case, and we don't handle these cases.

This will not allow us to achieve our goal of 99.999% reliability, especially given that we're also aiming at enterprise user's use cases.

Start by locating the Go orchestrator entry point that receives and processes segments, then read the related issue #885 for the batch-arrival case. Reproduce segments arriving faster than the assumed realtime interval and determine how multiple pending segments are handled. Done means the orchestrator reliably processes batched segments without losing the stated reliability goal.

Written by the indexing model from the issue text.