Support Puma lowlevel_error_handler

[tmaier]

You have a puma plugin. This is really great.

https://puma.io/puma/index.html#error-handling

It would be great, if the plugin would register directly a lowlevel_error_handler. Or alternatively, if you could document its usage at https://docs.appsignal.com/ruby/integrations/puma.html

Considerations/learnings from others:

• https://github.com/puma/puma/discussions/3135

[tombruijn]

Thanks for the suggestion! I hope it's not raised in the main Puma process because AppSignal is not active there, but if it's called in workers, we could maybe report it. It depends a bit on what kind of errors it tracks because we have gotten some reports recently of web server errors that we already report that a bunch of people don't want to track by default.

[tombruijn]

Added in Ruby gem 3.0.5!

[tmaier]

Thank you guys!