error-reporting

Noticed that sometimes miette is missing lines in the panic when you use Miette's custom handler.

Here's one example:

Miette:

  × Main thread panicked.
  ├─▶ at crates/nu-protocol/src/engine/stack.rs:46:9
  ╰─▶ variable not found
         0: 0x56147c2f1d38 - engine_q::main::h85b5921abc527ed0
                      at /home/jt/Source/engine-q/src/main.rs:185
         1: 0x56147c2ecf

This case should just be passed directly to the parent handler

Currently we use protobuf to document the representation format: https://github.com/soundcloud/periskop/blob/master/representation/errors.proto.

Since we are not planning to use protobuf as a serialization format, it would be more appropriate to use json schema instead.