[Orchestrion]: Enable Error Capture for Functions Returning Types Implementing error

[korECM]

Package Name

No response

Package Version(s)

No response

Describe the feature you'd like

I would like the dd-trace-go instrumentation to support error capture for functions whose return types implement the error interface, even if the return type is not explicitly defined as error.
This would involve extending the template helper (e.g., creating a helper like ResultHasError) to check whether a type implements error using something like types.Implements, rather than doing a strict type equality check.

Is your feature request related to a problem?

Yes, it is. Currently, when using the //dd:span tag, the error capture functionality only activates if the function’s return type is strictly error.

{{ with .Function.ResultOfType "error" -}}
  defer func(){
    span.Finish(tracer.WithError({{ . }}))
  }()
{{ else -}}
  defer span.Finish()
{{- end -}}

This causes issues when a function returns a different type (or an interface implementing error) since the error is not captured, leading to missing error reporting in spans.
As a workaround, users are forced to either change the function signature to return error explicitly or resort to manually handling errors with the dd-trace-go API.

Describe alternatives you've considered

No response

Additional context

This feature request was sparked by a discussion on the Orchestrion GitHub discussions.
I believe that modifying the dd-trace-go templates to allow error capture for types that implement error will improve usability for a broader range of scenarios.

I would be happy to work on this change if it's considered a worthwhile improvement by the maintainers.

[korECM]

This is the issue for adding ResultHasError function in orchestrion