Added PR template

Author: KittyChiu

.github/pull_request_template.md

@@ -0,0 +1,32 @@
+<!-- markdownlint-disable MD041 -->
+
+### What changed
+
+<!-- Briefly describe what this PR changes. -->
+
+### Why
+
+<!-- Explain the issue, request, or context this PR addresses. -->
+<!-- If applicable, link the related issue here using "Closes #ISSUE_NUMBER". Remove if not applicable. -->
+
+### Type of change
+
+<!-- Select all that apply. -->
+
+- [ ] Content Library article
+- [ ] Website code change
+- [ ] Documentation update
+- [ ] Other:
+
+### Contributors checklist
+
+<!-- Complete only what applies. -->
+
+- [ ] For Content Library changes: file name, directory, front matter, and writing style are appropriate
+- [ ] For website code changes: code standards, tests, dependencies, logging/debugging, and LICENSE impact were considered
+- [ ] For documentation updates: content is clear, accurate, consistent, and proofread
+- [ ] Related issue, discussion, or Content Request is linked, if applicable
+
+### Notes for reviewers
+
+<!-- Known gaps, follow-up work, or specific reviewer guidance. -->