docs: add contributing guide and issue/PR templates

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,21 @@
+<!--
+Thanks for your contribution! Please write this PR in English.
+【中文开发者】请使用英文填写，感谢 ❤️
+-->
+
+## What does this PR do?
+
+<!-- A short description of the change and why it's needed. -->
+
+## Type of change
+
+- [ ] Bug fix
+- [ ] New feature
+- [ ] Docs
+- [ ] Refactor / chore
+
+## Checklist
+
+- [ ] I tested this change locally
+- [ ] Code comments and docs are in English
+- [ ] Linked related issue (if any): closes #