fix(complement-race): add missing useRef import

- TypeScript error: Cannot find name 'useRef'
- Added useRef to React imports in Provider.tsx

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Co-Authored-By: Claude <noreply@anthropic.com>

apps/web/src/arcade-games/complement-race/Provider.tsx

@@ -11,6 +11,7 @@ import {
   useContext,
   useEffect,
   useMemo,
+  useRef,
   useState,
   type ReactNode,
 } from 'react'