feat: Add initial policy on LLM-generated contributions

.github/CODE_OF_CONDUCT.md

@@ -1,3 +1,21 @@
 # Code of Conduct
 
-[Contributor Covenant Code Of Conduct](https://www.contributor-covenant.org/version/2/1/code_of_conduct/).
+chezmoi follows the [Contributor Covenant Code Of
+Conduct](https://www.contributor-covenant.org/version/2/1/code_of_conduct/) with
+the following additions for LLM (Large Language Model)-generated contributions:
+
+* You may use any tools you wish to generate content for chezmoi.
+
+* You must review the content for correctness and legal obligations before
+  contributing it.
+
+* If you contribute un-reviewed LLM-generated content with the admission that
+  you do not understand the content then you will receive a warning. If you post
+  any un-reviewed LLM-generated content after the warning then you will be
+  banned without recourse.
+
+* If you contribute un-reviewed LLM-generated content without any admission that
+  you used an LLM then you will immediately be banned without recourse.
+
+Example LLMs include, but are not limited to, ChatGPT, Claude, Gemini, GitHub
+Copilot, and Llama.

assets/chezmoi.io/docs/developer-guide/index.md

@@ -1,5 +1,13 @@
 # Developer guide
 
+!!! warning
+
+    If you use an LLM (Large Language Model, like ChatGPT, Claude, Gemini, GitHub Copilot,
+    or Llama) to make a contribution then you must say so in your contribution and
+    you must carefully review your contribution for correctness before sharing it.
+    If you share un-reviewed LLM-generated content then you will be immediately
+    banned. See `CODE_OF_CONDUCT.md` for more information.
+
 chezmoi is written in [Go](https://golang.org) and development happens on
 [GitHub](https://github.com). chezmoi is a standard Go project, using standard
 Go tooling. chezmoi requires Go 1.22 or later.