Add page with AI code policy

[geekygirlsarah]

I've started seeing PRs on some projects I follow where people create solutions with AI, but they aren't great quality and often just leave placeholder statements. With Hacktoberfest coming up next month, I think I want an addition to the docs (or CONTRIBUTING.md or something) that outlines what will be accepted and what won't. I'm not opposed to code contributions that have used AI, but the hope would be it's still mostly human done and maybe AI assistance rather than just having it write the whole thing.

If anyone's following this, I'm open to input!