Add favicon, build job for euroe demo. #1

	name: 'Build and push the euroe demo'
	on:
	push:
	tags:
	- release/euroe-demo/..*

	workflow_dispatch: # allows manual trigger from main

	env:
	REGISTRY: docker.io
	IMAGE_NAME: dapps-euroe-demo

	jobs:
	publish-docker-image:
	runs-on: ubuntu-latest
	environment: testnet-deployments
	steps:
	- name: Checkout repository
	uses: actions/checkout@v4
	with:
	submodules: recursive
	# Uses the `docker/login-action` action to log in to the Container registry.
	- name: Log in to the Container registry
	uses: docker/login-action@65b78e6e13532edd9afa3aa52ac7964289d1a9c1
	with:
	registry: ${{ env.REGISTRY }}
	username: ${{ secrets.DOCKERHUB_USERNAME }}
	password: ${{ secrets.DOCKERHUB_TOKEN }}
	- name: Extract version tag from package.json
	id: meta
	run: \|
	export VERSION=$(jq -r .version apps/voting/package.json)
	export FULL_IMAGE_TAG="${{ env.REGISTRY }}/concordium/$IMAGE_NAME:$VERSION"
	echo "::notice FULL_IMAGE_TAG=${FULL_IMAGE_TAG}"
	# Make sure the image does not exist. Abort if we can retrieve any metadata.
	if docker manifest inspect ${FULL_IMAGE_TAG} > /dev/null; then
	echo "::error ${FULL_IMAGE_TAG} already exists"
	exit 1
	else
	# Store the full image tag into a tag variable for the following step.
	echo "tag=${FULL_IMAGE_TAG}" > "$GITHUB_OUTPUT"
	fi
	- name: Build and push Docker image
	uses: docker/build-push-action@f2a1d5e99d037542a71f64918e516c093c6f3fc4
	with:
	context: euroe-demo
	file: ./euroe-demo/scripts/Dockerfile
	push: true
	platforms: linux/amd64
	tags: ${{ steps.meta.outputs.tag }}

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