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.

Written by the indexing model from the issue text.