Agent Skills: loading-states

Audit an app's async surfaces and implement the right loading, progress, and empty states — skeleton screens, spinners, progress bars, first-use/no-results/error-empty views — chosen by expected latency and layout knowledge. Use when the user says 'add loading states', 'the page just goes blank while fetching', 'add a skeleton screen', 'users think it's frozen', 'spinner or skeleton?', 'design the empty state', 'zero state', or when reviewing an app whose fetches show nothing. Produces a loading/empty-state audit of every async surface plus the implemented components.