phsl / new-api

- Fix uptime service card bottom spacing by removing flex layout
- Replace IconRotate with IconSend for request count to better represent semantic meaning
- Add skeleton loading placeholders for all dashboard statistics with 500ms minimum duration
- Unify avgRPM and avgTPM calculation with consistent NaN handling
- Standardize skeleton usage across HeaderBar and Detail components with active animations
- Remove unnecessary empty wrapper elements in skeleton implementations
- Remove gradient styling from system name in header

The changes improve user experience with consistent loading states, better semantic icons,
and eliminate visual layout issues in the dashboard cards.