Suggestion: Use 'next-themes' for theme switching

[pavel-fokin]

Rely on the standard solution rather than a custom script. Not sure if I missed some extra logic in custom script.

‼️ I don't know how to test Reciept page.

• Maintaince. For example, prefer addEventListener over the deprecated addListener.
• Follows best practices.
• Easier integrate with theme on the components level

[ihomp]

The whole purpose of the script in [_document.js] that the right theme will be used right away before rendering.. so we don't have a "flash" of white or black background etc when refreshing the page, or when there is no cookie yet.

it's also good not to wait for mounted=true in many cases.

I wouldn't touch it what we have.. just to make sure we don't break all the edge cases we used to test relates to themes.

What is the reason for a change?