When entering the cloud backup page, the remote backup directory list only showed cached data and required a manual click of the refresh button to see new backup files. This change adds a TTL-based auto-refresh that fetches fresh data when the cache is older than 5 minutes.
Changes:
- Added refreshedAt tracking per cache key in persisted state
- Added REMOTE_BROWSER_REFRESH_TTL_MS (5 min) constant
- Added useEffect that triggers auto-refresh when destination is selected and cached data is stale
- Stamped refresh timestamps after successful API responses
- Cleaned up timestamps on destination delete and settings save