Add devcontainer config

.devcontainer/Dockerfile

@@ -0,0 +1,6 @@
+FROM debian:stable
+ARG DEBIAN_FRONTEND=noninteractive
+ARG XDEBUG_MODE=coverage
+RUN apt update -y && apt install -y git composer php-cli php-dom php-curl php-xdebug vim
+WORKDIR /app
+CMD cd /app/generator/doc && ./update.sh && cd /app/generator && composer install && php ./safe.php generate && composer cs-fix

.devcontainer/build.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+cd $(dirname $0)/../
+docker run --rm -v ${PWD}:/app $(docker build -q -f .devcontainer/Dockerfile .)

.devcontainer/devcontainer.json

@@ -0,0 +1,10 @@
+{
+	"name": "Safe PHP",
+	"build": {
+		"context": "..",
+		"dockerfile": "./Dockerfile"
+	},
+
+	"workspaceMount": "source=${localWorkspaceFolder},target=/app,type=bind",
+	"workspaceFolder": "/app"
+}

.devcontainer/run.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+cd $(dirname $0)/../
+docker run --rm -ti -v ${PWD}:/app $(docker build -q . -f .devcontainer/Dockerfile) /bin/bash

CONTRIBUTING.md

@@ -2,6 +2,19 @@
 
 Safe-PHP code is generated automatically from the PHP doc.
 
+## Install dependencies
+
+### With a devcontainer
+
+If you use VSCode or similar, opening the project folder should prompt you to
+re-open the folder inside a docker container with all the relevant tools
+pre-installed.
+
+### Manually
+
+- php8.2+ CLI (with dom and curl modules)
+- composer
+
 ## How to install Safe-PHP development environment
 
 The first step is to download the PHP documentation project locally, using git.