* [clsi] Forward pandoc errors to web
* [clsi] Remove unused import
* [clsi] Align warning logs
* [clsi] Update HTTP response for errors
* [clsi] Update acceptance test with 422
* [clsi] Always return json body on 422
* [clsi] Include stderr in logs for non user facing errors
GitOrigin-RevId: 4284c8d4e8b7b45eac4997cd9e52ca4894b20412