feat(dev): add devcontainers setup

Author: akalipetis

.devcontainer/Dockerfile

@@ -0,0 +1,29 @@
+FROM php:7.4-cli
+
+# Install system dependencies
+RUN apt-get update && apt-get install -y \
+    zip \
+    unzip \
+    git \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Composer
+RUN php -r "copy('https://getcomposer.org/installer', 'composer-setup.php');" \
+    && php composer-setup.php \
+    && mv composer.phar /usr/local/bin/composer \
+    && php -r "unlink('composer-setup.php');" \
+    && chmod +x /usr/local/bin/composer
+
+# Create a non-root user
+ARG USERNAME=upsun
+ARG USER_UID=1000
+ARG USER_GID=$USER_UID
+
+RUN groupadd --gid $USER_GID $USERNAME \
+    && useradd --uid $USER_UID --gid $USER_GID -m $USERNAME \
+    && apt-get update \
+    && apt-get install -y sudo \
+    && echo $USERNAME ALL=\(root\) NOPASSWD:ALL > /etc/sudoers.d/$USERNAME \
+    && chmod 0440 /etc/sudoers.d/$USERNAME
+
+USER $USERNAME

.devcontainer/devcontainer.json

@@ -0,0 +1,8 @@
+{
+    "name": "Upsun CLI",
+    "build": {
+        "dockerfile": "Dockerfile"
+    },
+    "remoteUser": "upsun",
+    "postCreateCommand": "composer install"
+}