docs: guidelines for pr descriptions (@fehmer) (monkeytypegame#7706)

Author: fehmer

.github/pull_request_template.md

@@ -1,6 +1,16 @@
 ### Description
 
-<!-- Please describe the change(s) made in your PR -->
+<!-- 
+  Please describe the change(s) made in your PR:
+  - explain the problem being solved
+  - for bug fixes without an open issue, include steps to reproduce the issue
+  - summarize the approach taken
+  
+  Use your own words. Do not rely on AI-generated descriptions. 
+  They do not demonstrate your understanding of the problem or the solution.
+  Writing the description yourself helps you verify the scope of your work and 
+  helps us better understand your intent, reasoning and level of insight.
+-->
 
 ### Checks