React's usePrevious Hook: Fixing the Classic Recipe's Hidden Bug

The common usePrevious hook in React, which uses a ref and useEffect, can return stale values when a component re-renders for unrelated reasons. A new implementation from @reactuses/core tracks the previous distinct value instead of the previous render's value, using a pattern recommended by React docs. The fix is just twelve lines of TypeScript but has a gotcha that can cause infinite loops.