[Go] Bring Go Reflection API error handling to parity with JS

[apascal07]

Catch errors and return a standardized format that the Runner can unwrap.

[apascal07]

@alonsopec89 Please take a look at the error format that the JS runtime returns (it's an error wrapped in an object with multiple fields that the CLI runner then unwraps and makes useful) and make it the same in Go. Right now Go just returns a flat error which doesn't display nicely in the Dev UI AFAIK. Please make sure to repro/test this.