fix: add pull-requests write permission to docs workflow

GitHub Actions workflow was failing with "Resource not accessible by integration"
error when trying to comment on PRs. Added pull-requests: write permission to
allow the pr-comment job to create/update comments on pull requests.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: JnyJny

.github/workflows/docs.yml

@@ -21,6 +21,7 @@ permissions:
   contents: read
   pages: write
   id-token: write
+  pull-requests: write
 
 # Allow only one concurrent deployment, skipping runs queued between the run in-progress and latest queued.
 concurrency: