phase 1: add Gemfile pinned to github-pages for reproducible local builds #3

	name: site-health

	on:
	pull_request:
	paths:
	- '*.html'
	- '*.md'
	- '_layouts/**'
	- '_includes/**'
	- '_config.yml'
	- '_data/**'
	- '_posts/**'
	- 'images/**'
	- 'css/**'
	- 'js/**'
	- 'Gemfile'
	- 'Gemfile.lock'
	- 'lychee.toml'
	- '.html5validator.yaml'
	schedule:
	# Weekly Monday 9am UTC, matching update-publications cadence.
	- cron: '0 9 * * 1'
	workflow_dispatch:

	jobs:
	site-health:
	runs-on: ubuntu-latest

	steps:
	- name: Checkout repository
	uses: actions/checkout@v4

	- name: Set up Ruby
	uses: ruby/setup-ruby@v1
	with:
	ruby-version: '3.3'
	bundler-cache: true

	- name: Build site
	run: bundle exec jekyll build

	- name: Check links with lychee
	uses: lycheeverse/lychee-action@v2
	with:
	args: --config ./lychee.toml --no-progress _site
	fail: true

	- name: Validate HTML
	uses: Cyb3r-Jak3/html5validator-action@v7.2.0
	with:
	root: _site/
	config: .html5validator.yaml

Provide feedback