areRenderRelevantPartsEqual did not compare the tool part output field,
so when the AI updated a todo list (e.g., marking items completed) the
ToolPart memo comparator returned true and skipped re-render. The UI
stuck showing stale task status.
Fix: add output reference comparison for tool parts in
areRenderRelevantPartsEqual so streaming tool output updates trigger
re-renders correctly.
Co-authored-by: Shyamalan Kannan <yabuku@Shyamalans-MacBook-Pro.local>
