Write workflow test run report schema

## Summary
Create a schema for workflow test execution results.

## Molds that will link it
- `run-workflow-test` as output schema
- `debug-galaxy-workflow-output` as input schema
- `implement-galaxy-workflow-test` as feedback input

## Notes
- Include command, environment, exit code, failing output labels, assertion failures, logs, invocation id, and artifact paths.

Start by locating the definitions for the run-workflow-test, debug-galaxy-workflow-output, and implement-galaxy-workflow-test molds. Use the listed execution details as the required schema fields, then verify that the schema can serve as the output and input connections described and represents failing outputs, assertions, logs, and artifacts consistently.

Written by the indexing model from the issue text.