Experiment adding OpenTelemetry Python style exception recording to OpenTelemetry Elixir

tracer.ex

defmodule OpenTelemetry.Tracer do
  # ...

    quote do
      span_ctx = unquote(span_ctx)

      {exception_opts, start_opts} =
        unquote(start_opts)
        |> Map.new()
        |> Map.split([:record_exception, :set_status_on_exception])

      start_opts =
        Map.merge(start_opts, %{record_exception: false, set_status_on_exception: false})

      try do
        :otel_tracer.with_span(
          span_ctx,
          :opentelemetry.get_tracer(__MODULE__),
          unquote(name),
          start_opts,
          fn _ -> unquote(block) end
        )
      rescue
        exception ->
          if not match?(%{record_exception: false}, exception_opts) do
            OpenTelemetry.Span.record_exception(span_ctx, exception, __STACKTRACE__)
          end

          if not match?(%{set_status_on_exception: false}, exception_opts) do
            status = OpenTelemetry.status(:error, Exception.message(exception))
            OpenTelemetry.Span.set_status(span_ctx, status)
          end

          reraise exception, __STACKTRACE__
      end
    end
    
  # ...
end

Experiment adding OT Python style opt-out record_exception and set_status_on_exception start options to OT Elixir's with_span/4. Most of the mess is in the capabilities being conditional, and turning both off for the inner otel_tracer:with_span/5 so exceptions don't get recorded twice.

Removed delegation to Tracer. with_span_exception/4. Contains if, which'll have some maintainers breaking out in a rash, but it strikes me as closer to the house code style.