Feat. `!circular-import` command with a guide to avoid circular imports just like `!return`

[ShubhamVG]

A lot of beginners encounter circular import error so often so that it would be nice && wise to have a command like !circular-import just like !return giving the user examples or bullet points to avoid circular imports or suggesting them resourced to check out.

I'm not well versed with this myself so I don't have a proposed implementation. Someone else with have to come up with or decide what content the !circular-import command will hold. However, I suggest that whatever it contains should be versatile and not just a solution for python (preferably).