godelski said your resume should really be GitHub. You could have said this instead of sarcasm.
If I had a company I'd offer looking over an existing project or a project where you create a side project of your choice without any further direction.
So not mandatory but the easiest way to go probably. Once you apply to my company you'll have one to show for next time at least.
(If you want to write the project out on the whiteboard instead I guess feel free, that seems hard though.)
I think it's more useful and more fair to give candidates some direction when I request something. What scope is enough? What tests are enough? We define side project differently or you would expect much more time from candidates than I do.
How each candidate answers each question themselves tells you about them.
I think a side project opens up the opportunity to skip that for a project presentation. This is a lot more in line with real life as you would typically code and later present that work to others. You would defend it to some degree, why you made choice A vs choice B. If you created it, you'll be able to do that.
Doesn't need to be a huge thing. Just show you can do anything at all really at the junior level. Intermediates can show mastery in a framework with something with slightly more complexity than a "hello world".