Return 500 and a body when the application crashes

[lpil]

Hello!

Currently when the web handler crashes the connection is closed. I think we would want to instead return 500 and a body, perhaps Internal server error.

We would also want to ensure that the error is logged using the Erlang logger.

[rawhat]

Wrapped the call to the HTTP handler in a gleam/erlang.{rescue} 🎉

Also added a super small wrapper around the logger:error method. Works in the interim, until we decide on anything more robust!

[lpil]

Brill, thank you