Utility script to clean up import data from the database after testing /import/dry-run. Useful for re-running the import process during development and QA. Deletes all animals and litters created by the import (identified by ImportSource='docx-export' and ImportSource='derived-litter'), resets sequences, and leaves the database ready for fresh import execution. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>