The runs_list.tmpl used old class names (flex-list, flex-item,
flex-item-leading, flex-item-main, flex-item-trailing, flex-item-title,
flex-item-body) that no longer exist in the CSS. The shared flex-list
stylesheet was refactored to use flex-divided-list, items-with-main,
item, item-leading, item-main, item-trailing, item-title, item-body.
Without matching CSS, the Actions runs list lost all flex layout — items
were not displayed as proper rows.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>