rework LLM section as per mlpack

CONTRIBUTING.md

@@ -6,10 +6,6 @@ a pull request with an improvement, bugfix, or feature addition, and an
 ensmallen maintainer will review it and help through the merge process.  So if
 you have an improvement you would like to see, we would love to include it!
 
-ensmallen does not accept any source code which has been created
-(directly or indirectly) with the aid of Large Language Models (LLMs).
-This is due to unclear code provenance and questionable quality of LLM generated code.
-
 The ensmallen maintainer community overlaps heavily with the
 [mlpack](https://github.com/mlpack/mlpack) community, so development discussions
 can happen either here on Github or in the `#mlpack:matrix.org` channel on
@@ -17,6 +13,23 @@ can happen either here on Github or in the `#mlpack:matrix.org` channel on
 [here](https://www.mlpack.org/doc/developer/community.html) for more
 information.
 
+## Usage of LLMs / Coding Assistants
+
+Each contributor needs to understand the content they are proposing for ensmallen,
+and how the proposed content changes and/or expands functionality in ensmallen.
+Content includes source code, documentation, and other material such as images
+and datasets.  The pull request must justify the proposed content in the
+description.  Using coding assistants or tools like Large Language Models (LLMs) 
+does not grant additional privileges or reduce our expectations.
+
+Each contributor is responsible for the proposed content, regardless of where
+the content came from.  The responsibility includes ensuring that the content
+can be submitted to ensmallen and does not violate intellectual property rights
+such as copyright(s).  Source code in ensmallen is licensed under the BSD license;
+see `LICENSE.txt` for details.
+
+## Pull request process
+
 Once a pull request is submitted, it must be reviewed and approved before a
 merge, to ensure that: