Improved performance of loading games from Chess.com/Lichess

[codeswhite]

• Automatically load the latest stored username from the storage
• Render query data from react-query cache (by using isLoading instead of isFetching)
• Set the username typing debounce delay to 450 for both CC and Lichess

[GuillaumeSD]

Thanks for your PR @codeswhite, I'll handle it when I have some time available.