Update readme with no-AI clause

Also removing bounty offering. We haven't done this for a while and now
it looks to be becoming a honeypot for AI agents.

Author: peppy

README.md

@@ -8,7 +8,7 @@ Contributions can be made via pull requests to this repository. If you're unsure
 
 Note that while we already have certain standards in place, nothing is set in stone. If you have an issue with the way code is structured; with any libraries we are using; with any processes involved with contributing, *please* bring it up. I welcome all feedback so we can make contributing to this project as pain-free as possible.
 
-We love to reward quality contributions. If you have made a large contribution, or are a regular contributor, you are welcome to [submit an expense via opencollective](https://opencollective.com/ppy/expenses/new). If you have any questions, feel free to [reach out to peppy](mailto:pe@ppy.sh) before doing so.
+Our team believes in **human contributions**. Any contribution – be it an issue report or a pull request – which is created by, documented by, or aided by AI/LLM usage will typically be **closed and locked without further discussion**.
 
 # Licence