Update to Aivana Database Engineer

{
  "name": "rollback-rehearsal-engine",
  "description": "Creates rollback rehearsal steps and proof checklist for database changes.",
  "included_files": [],
  "skill_md_contents": "---\nname: rollback-rehearsal-engine\ndescription: Creates rollback rehearsal steps and proof checklist for database changes.\n---\n\n# Rollback Rehearsal Engine\n\nRun:\n\n```bash\nnode runtime/runTool.js rollback_rehearsal_engine '{\"change\":\"CREATE INDEX ix_orders_status ON orders(status)\",\"rollback\":\"DROP INDEX ix_orders_status\",\"validationQueries\":[\"SELECT count(*) FROM orders\"]}'\n```\n\nReturns rehearsal status and ordered rollback validation steps.\n"
}