Add contribution guidelines #19

	name: Build & test
	on:
	pull_request:
	branches: [main]
	jobs:
	build:
	name: Build and verify stack
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v4
	- name: Setup environment
	run: \|
	cp .env-example .env
	- name: Build and start the stack
	run: \|
	docker compose up --build -d
	- name: Verify that the stack is running
	run: \|
	bash ci-verify.sh
	if [ $? -ne 0 ]; then
	docker compose logs
	exit 1
	fi
	shell: bash

Provide feedback