policy: Added to the PR template, and an AGENTS.md, refusing AI contributions.

Fixes #15350.

(cherry picked from commit 08285d828efcb03c2c373289810ab62d4487a7a2)

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,3 +1,12 @@
+<!--
+PLEASE NOTE THAT WE DO NOT ACCEPT ANY CODE THAT WAS AI-GENERATED.
+
+IF AN AI AGENT WROTE OR ASSISTED IN THE WRITING OF YOUR CODE, DO NOT OPEN A PR.
+
+THANK YOU.
+-->
+
+
 <!--- Provide a general summary of your changes in the Title above -->
 
 ## Description

AGENTS.md

@@ -0,0 +1,11 @@
+The SDL project does not accept contributions that are in any part created by
+AI agents.
+
+We reject any pull requests that have any amount of code generated by an LLM,
+generative AI, or anything other than a human being.
+
+Any code that was produced this way must be disclosed when submitting it to
+the project.
+
+Thank you!
+