The contract test in test_character_animation_pipeline.py asserts
result.success after the QA run, implying success should reflect
whether QA passed. But CharacterAnimationReviewer always returned
success=True even when issues were found and status was 'revise'.
This creates a silent failure path: callers that gate on result.success
(the standard ToolResult contract) would treat a broken rig as a clean
pass without ever reading report['status'].
Fix: return success=not issues so result.success is False when QA finds
problems, consistent with the test contract and with how execution errors
are already handled (success=False on exception paths).
Also adds test_character_reviewer_success_false_when_qa_finds_issues to
explicitly assert this contract — a broken rig with missing joints must
produce status='revise', non-empty issues[], and success=False.
7cd7199986