Automated long read status run

[mrmonkington]

Write a daemon to sit on the watch_protocol_run API and post slack messages when state changes:

https://github.com/nanoporetech/minknow_api/blob/master/proto/minknow_api/protocol.proto#L109

Some useful prior art:

• https://github.com/lysovosyl/NanoDeep/blob/main/read_until/read_until_utils.py#L22

(Daemonise with systemd service)