Persist nats data

[edilmedeiros]

In preparation for the use of Jetstream and a follow up from #10, we probably want to persist nats in a folder we can control instead of let docker decide what to do.

[m4ycon]

Will we use jetstream? To make nats persistence work some code changes are required, not that it is complex, the minimun is to create a jetstream stream and start nats with a custom config. My question is more about the path that peer-observer is taking when we talk about persistence (as discussed in peer-observer/peer-observer#121).

[edilmedeiros]

I think Jetstream will be beneficial anyhow because it allows tools to recover from failures by not missing the events.
But let's work on other stuff and get back here when/if this becomes more relevant.