Scoring is only meaningful for LLM-backed steps. Preprocess tests are deterministic Python, so scores add no value. Kept only for detect tests. - test_preprocess: drop _lf_score call, simplify _run_assertions return type - cases.yaml: remove score_name from all op=preprocess entries Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>