Local useState resets to 0 every time phase transitions from 'generating' back to 'detailing', causing the view to snap back to branch 1. Move viewingIndex to store's currentBranchIndex (already existed) and advance it in generateBranchDetail after success. Component reads from store so remounts no longer lose position. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>