fix: CI Docker tags must be lowercase, upgrade docker actions #4

	name: CI

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

	env:
	REGISTRY: ghcr.io
	IMAGE_PREFIX: ghcr.io/rwx-g/stackoverkill.io

	jobs:
	validate:
	name: Lint, Typecheck & Test
	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v5

	- uses: pnpm/action-setup@v4

	- uses: actions/setup-node@v5
	with:
	node-version: 20
	cache: pnpm

	- name: Install dependencies
	run: pnpm install --frozen-lockfile

	- name: Build shared package
	run: pnpm --filter @stackoverkill/shared build

	- name: Lint
	run: pnpm lint

	- name: Typecheck frontend
	run: pnpm --filter @stackoverkill/frontend exec tsc --noEmit

	- name: Typecheck backend
	run: pnpm --filter @stackoverkill/backend exec tsc --noEmit

	- name: Test
	run: pnpm test

	build-docker:
	name: Build Docker Images
	runs-on: ubuntu-latest
	needs: validate
	if: github.ref == 'refs/heads/main'

	permissions:
	contents: read
	packages: write

	steps:
	- uses: actions/checkout@v5

	- name: Log in to GitHub Container Registry
	uses: docker/login-action@v4
	with:
	registry: ${{ env.REGISTRY }}
	username: ${{ github.actor }}
	password: ${{ secrets.GITHUB_TOKEN }}

	- name: Build & push frontend image
	uses: docker/build-push-action@v7
	with:
	context: .
	file: docker/frontend.Dockerfile
	push: true
	tags: \|
	${{ env.IMAGE_PREFIX }}/frontend:latest
	${{ env.IMAGE_PREFIX }}/frontend:${{ github.sha }}

	- name: Build & push backend image
	uses: docker/build-push-action@v7
	with:
	context: .
	file: docker/backend.Dockerfile
	push: true
	tags: \|
	${{ env.IMAGE_PREFIX }}/backend:latest
	${{ env.IMAGE_PREFIX }}/backend:${{ github.sha }}

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