Revise PR review instructions for clarity and scope

Updated instructions for reviewing pull requests to clarify the scope and expectations for human-authored changes.

.github/pr-review.instructions.md

@@ -1,2 +1,18 @@
-When reviewing pull requests, skip and ignore any pull request whose source branch name starts with "auto-merge/".
-Please don't make any comments, suggestions, summaries, or reviews for these pull requests.
+# Pull Request Review – GitHub Copilot Instructions
+
+> **Scope**: Pull request reviews in this repository.
+>
+> **Goal**: Avoid generating noise on machine-generated or automatically merged pull requests, and focus reviews on human-authored changes that require design or code feedback.
+
+---
+
+## Review Scope Filtering
+
+- When reviewing pull requests, **skip and ignore any pull request whose source branch name starts with `auto-merge/`**.
+- Do **not** generate review comments, suggestions, summaries, or approvals for these pull requests.
+- Treat these pull requests as machine-generated and out of scope for AI review.
+
+## Review Expectations (Applicable PRs Only)
+
+- Only review pull requests created from human-authored feature, bugfix, or maintenance branches.
+- Provide feedback that focuses on correctness, design quality, maintainability, and alignment with existing repository conventions.