Create pull_request_template.md

Author: charlesvien

.github/pull_request_template.md

@@ -0,0 +1,15 @@
+## Problem
+
+<!-- Who is this for and what problem does it solve? -->
+
+<!-- Closes #ISSUE_ID -->
+
+## Changes
+
+<!-- What did you change and why? -->
+<!-- If there are frontend changes, include screenshots. -->
+
+## How did you test this?
+
+<!-- Describe what you tested -- manual steps, automated tests, or both. -->
+<!-- If you're an agent, only list tests you actually ran. -->