Redux Persist

Summary

A library that automatically saves your Redux store to storage (like localStorage) and rehydrates it on page load, so state survives refreshes.

• 1Add Redux Persist to a Redux Toolkit store and confirm state survives a refresh.
• 2Learn `whitelist`/`blacklist` config to persist only specific slices.
• 3Understand the rehydration flow and why there's often a brief 'loading' state on startup.