test_prepared_group_is_used_without_refetching had a tautological final
assertion; now checks stream.calls directly. test_no_partial_letter_at_either_edge
required both crop edges to be blank, but the left edge here is always the
crop's start position with no lead-in gap in word_strip, so it legitimately
carries ink — only the right edge is an actual cut and needs the check.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KEZK1P1Q1fu5pcuVrkrCFZ