This pull request refactors and optimizes the way network and validator statistics are fetched and processed in the admin UI, particularly in the useNetworkStats hook. The changes consolidate multiple backend requests into a single call, ensure only relevant data for installed clients is fetched, and improve the reliability and efficiency of the dashboard. Additionally, there are minor improvements and cleanup in system health reporting.

Network and Validator Data Refactor:

• Refactored useNetworkStats to fetch validator data (active, attesting, balances) in a single backend call (validatorsDataByNetwork), reducing the number of beacon chain API requests and simplifying state management. Also, the hook now dynamically determines which networks have installed clients before fetching data, ensuring only relevant information is retrieved and displayed. [1] [2] [3] [4] [5] [6]

• Updated the mock backend (__mock-backend__/index.ts) to provide the new combined validatorsDataByNetwork response structure, replacing the previous separate endpoints for active, attesting, and balances.

System Health Improvements:

• Fixed the formatting of memory and disk usage in useSystemHealth to use the correct arguments for humanFileSize, ensuring consistent display of units.

Code Cleanup and Removal:

• Removed the old implementation of useSystemHealth.ts, which is now superseded by the improved version.

Type and Utility Improvements:

• Added a type guard utility isClientError to help distinguish error results from valid client results.
• Updated imports and usage in dashboard components to use the new utility.