#skip-bugbot

<!-- This is an auto-generated description by cubic. -->
---
## Summary by cubic
Automates Playwright result comments in CI to make failures easier to
spot and fix. Adds missing-shard warnings, collapsible failure lists,
and copy-paste snapshot update commands.

- **New Features**
- Adds a GitHub Actions step to run
scripts/generate-playwright-summary.js via github-script (uses
PLAYWRIGHT_RUN_ID).
- Detects missing macOS/Windows shards from blob reports and shows a
warning in the PR comment.
- Collapsible failure sections when there are more than 10 failures per
OS.
- Generates copy-paste npm commands to update snapshots for failed macOS
tests.
- Supports workflow_run and pull_request events; handles push events
without a PR gracefully.

<sup>Written for commit ccafd00835b5390949ca18a8743c6c69a44b21d4.
Summary will update on new commits.</sup>

<!-- End of auto-generated description by cubic. -->