It’s not forbidden to use LLM for Haiku development. The rule just says one should ensure that no code with ambiguous or incompatible licenses are contributed:
“The Haiku project cannot accept contributions (e.g. code, documentation, translations, etc.) which are under ambiguous or incompatible licenses. (This includes most content produced with the use of LLMs.)”
PulkoMandy explained it quite well here: Shhh... Haiku isn't blind anymore! - #41 by PulkoMandy
The policy only says that you have to make sure there are no copyright violations, not that AI is banned outright.
Reading the generated AI code and writing something based on it would be fine (just as we often have a look at gpl driver code in Linux for reference, but we don’t directly copy it).
Searching the web for cooe snippets to make sure they are original and not copypasted from somewhere else would also satisfy the policy. Don’t make it more extreme than it is.