Add blog CI checks pipeline

[wuchong]

No description provided.

[Copilot]

Pull request overview

Adds a GitHub Actions workflow intended to run CI checks for the blog on pushes and PRs targeting main.

Changes:

• Introduces a new Check Blog workflow triggered on push and pull_request to main.
• Checks out the repo, sets up Node.js, installs dependencies, and runs a Docusaurus build.

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[Copilot]

The header comment says this workflow checks broken links, but the job only runs docusaurus build and the site config currently sets onBrokenLinks: 'warn', so broken links won't fail CI. Either update the description to match (build-only) or adjust the build/link-checking so broken links cause a failure (e.g., CI-specific onBrokenLinks: 'throw').

Suggested change

	# This workflow is meant for checking broken links in the blog.
	# This workflow is meant for validating that the blog builds successfully.

[Copilot]

CI uses npm install but the repo doesn't include a lockfile, which makes dependency resolution non-deterministic and can cause flaky builds over time. Consider committing a lockfile (package-lock.json) and switching CI to npm ci for reproducible installs (and enabling setup-node caching once a lockfile exists).

Suggested change

	run: npm install
	run: |
	if [ ! -f package-lock.json ]; then
	echo "package-lock.json is required for reproducible CI installs. Commit the lockfile and rerun."
	exit 1
	fi
	npm ci

[Copilot]

Job id test-deploy is misleading in a workflow named "Check Blog" (it neither tests nor deploys). Renaming it to something like build/check makes the Actions UI and logs easier to interpret.

Suggested change

	test-deploy:
	check: