[llvm] [docs] Strengthen our quality standards and connect AI contribution policy to it (PR #154441)

[Hubert Tong via llvm-commits]

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@@ -107,6 +72,14 @@ from the book [Working in Public][public] by Nadia Eghbal:
 > contribution, it might be a pull request that's too complex or unwieldy to
 > review, given the potential upside.\" \-- Nadia Eghbal
 
+Prior to the advent of LLMs, open source project maintainers would often review
+any and all changes send to the project simply because posting a change for
----------------
hubert-reinterpretcast wrote:

```suggestion
any and all changes sent to the project simply because posting a change for
```

https://github.com/llvm/llvm-project/pull/154441