Add plugins matrix job to CI for tsc, lint, prettier, and build (#15) #2

	name: CI plugins

	on:
	push:
	branches: [main]
	pull_request:
	branches: [main]

	permissions:
	contents: read

	jobs:
	plugins:
	runs-on: ubuntu-latest

	strategy:
	fail-fast: false
	matrix:
	workspace:
	- backstage-1.42
	- backstage-1.45
	# - backstage-1.49
	# - backstage-1.52

	steps:
	- name: Harden runner
	uses: step-security/harden-runner@v2
	with:
	egress-policy: audit

	- name: Checkout
	uses: actions/checkout@v7

	- name: Setup Node.js
	uses: actions/setup-node@v4
	with:
	node-version-file: plugins/${{ matrix.workspace }}/package.json

	- name: Install dependencies
	run: yarn install --immutable
	working-directory: plugins/${{ matrix.workspace }}

	- name: TypeScript type check
	run: yarn tsc
	working-directory: plugins/${{ matrix.workspace }}

	- name: Lint
	run: yarn lint:all
	working-directory: plugins/${{ matrix.workspace }}

	# - name: Check formatting
	# run: yarn prettier:check
	# working-directory: plugins/${{ matrix.workspace }}

	- name: Build
	run: yarn build:all
	working-directory: plugins/${{ matrix.workspace }}

	- name: Verify no changes in .github/
	run: \|
	if [ -n "$(git status --porcelain .github/)" ]; then
	echo "::error::Unexpected changes detected in .github/ after CI steps:"
	git diff .github/
	exit 1
	fi
	echo "No changes in .github/ — OK"

	plugins-check:
	if: always()
	needs: plugins
	runs-on: ubuntu-latest

	steps:
	- name: Harden runner
	uses: step-security/harden-runner@v2
	with:
	egress-policy: audit

	- name: Verify all plugin matrix jobs passed
	run: \|
	if [ "${{ needs.plugins.result }}" != "success" ]; then
	echo "::error::One or more plugin matrix jobs failed"
	exit 1
	fi

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