docs: document dependency setup

setup.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+set -e
+
+check_cmd() {
+  command -v "$1" >/dev/null 2>&1
+}
+
+apt_packages=()
+
+if ! check_cmd jq; then
+  apt_packages+=(jq)
+fi
+
+if ! check_cmd qrencode; then
+  apt_packages+=(qrencode)
+fi
+
+if ! check_cmd convert; then
+  apt_packages+=(imagemagick)
+fi
+
+if ! check_cmd pdftotext; then
+  apt_packages+=(poppler-utils)
+fi
+
+if ! check_cmd node || ! check_cmd npm; then
+  apt_packages+=(nodejs npm)
+fi
+
+if [ ${#apt_packages[@]} -gt 0 ]; then
+  echo "Installing system packages: ${apt_packages[*]}"
+  sudo apt-get update
+  sudo apt-get install -y "${apt_packages[@]}"
+fi
+
+for pkg in javascript-obfuscator html-minifier-terser; do
+  if ! check_cmd "$pkg"; then
+    npm install -g "$pkg"
+  fi
+done
+
+echo "All dependencies are installed."