refactor yaml sql test case

**Is your feature request related to a problem? Please describe.**

there is `cases/plan/error_unsupport_sql.yaml`, but might better to put some of those case together with the happy ones.

**Describe the solution you'd like**

- add yaml syntax doc
- support fail assert
- support which phase to fail so e.g `runner_test` can filter on this. ( refactor over `mode` key ? )
- assert fail message
- test code need tweaks

**Additional context**

- backward compatibility

Look at the test file `cases/plan/error_unsupport_sql.yaml` to understand its current structure. Examine how SQL test cases are run, likely in `runner_test` or similar test suites. The goal is to merge error cases with happy-path cases by adding fail assertions and phase specifications, while maintaining backward compatibility. Check for existing documentation on the YAML syntax to update.

Rédigé par le modèle d'indexation à partir du texte de l'issue.