## Summary
- Fixes the merge-reports workflow failure on fork PRs (like #2276)
- Wraps GitHub API calls in try-catch to handle 403 permission errors
gracefully
- Test results are still written to the job summary even when PR comment
fails

## Test plan
- [x] Verify the fix by checking the merge-reports job on this PR
(should pass)

#skip-bugbot

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

<!-- This is an auto-generated description by cubic. -->
---
## Summary by cubic
Prevents merge-reports from failing on fork PRs by gracefully handling
403 permission errors when posting Playwright results. Test results
still appear in the job summary even if the PR comment can’t be created
or updated.

- **Bug Fixes**
- Wrap PR comment API calls in try/catch; on 403, log a clear message
and continue without failing the workflow.
- Keep update/create logic for the bot comment when permissions allow;
skip safely when no PR is detected.

<sup>Written for commit befdb30e68a21ddb992e0d175d91352dfe8e04e0.
Summary will update on new commits.</sup>

<!-- End of auto-generated description by cubic. -->
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>