Consider adding a policy banning LLM contributions

[Ember-ruby]

as more and more projects show that they don't care about code quality, the environment, people's lives, even their own skills, etc it's especially important that the ones that do care show it

for prior work on policies like this see:
https://codeberg.org/ziglang/zig#strict-no-llm-no-ai-policy
https://github.com/florisboard/florisboard/blob/main/AI_POLICY.md
https://asahilinux.org/docs/project/policies/slop/
https://codeberg.org/superseriousbusiness/gotosocial/src/branch/main/CODE_OF_CONDUCT.md