Add metrics for the events in the network output channels (#5597)

* Add metrics for the events in the network output channels

* Documentation fixes

* A couple fixes

* Fix panic at destruction

* Rework for direct Prometheus integration

* Don't lock on the Receiver

* Another review address

* Address review

* Update client/network/src/service/out_events.rs

Co-Authored-By: Max Inden <mail@max-inden.de>

* Fix bad event name

* Fix descriptions

* Fix names

* client/network/service/out_events: Apply remaining suggestions

Co-authored-by: Max Inden <mail@max-inden.de>