Format output as json and return the hashcode from relevant commands

[tal-sapan]

Checklist

• [X] Code compiles correctly
• [x] Relevant tests were added (unit / contract / integration)
• [X] Relevant logs were added
• [X] Formatting and linting run locally successfully
• [X] All tests passing
• [ ] UA review
• [ ] Design is documented
• [ ] Extended the README / documentation, if necessary
• [ ] Open source is approved

[tal-sapan]

The reduced coverage is due to error handling when an error message cannot be serialized to json. I can't think of a way to test it.