[proposal] customizable YAML output

[eddie-knight]

Is your feature request related to a problem?

right now we have a complex YAML output for each run. the payload object alone is quite large. And because we put multiple run results in one file, it's not a gemara-compatible output.

Describe the solution you'd like

We should allow users to tune their output results further.

1. This may be by simply omitting payload (or using a flag to include it as tracing info)
2. For gemara-compatible results, we'd need to rearrange the output a bit. To avoid making a breaking change, we'd need to add a gemara option in addition to the current yaml which will remain unchanged

Describe alternatives you've considered

No response

Additional context

No response