Refactor deployment scripts to improve Node.js version handling and PM2 process management

- Updated `ensure_node_version` function in `deploy-production.sh` and `deploy-test.sh` to use a common script for Node.js version validation.
- Simplified PM2 instance restart logic by introducing `deploy_restart_pm2` function in a new `deploy-runtime.sh` script.
- Replaced direct PM2 commands with the new function to handle instance restarts and HTTP readiness checks.
- Modified PM2 configuration files to set the script directly instead of using `node` as the interpreter, allowing for better compatibility with older Node.js versions.
- Added tests for the new deployment runtime functions in `deploy-runtime.spec.ts` to ensure correct behavior during deployment.
- Updated `package-lock.json` to include new dependencies and ensure compatibility with the latest changes.

scripts/deploy-runtime.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+# Sourced by the test and production deployment scripts.
+
+deploy_restart_pm2() {
+  local instance_name="$1"
+  local config_file="$2"
+  local node_binary
+
+  if [ ! -f "$config_file" ]; then
+    echo "ERROR: PM2-Konfigurationsdatei nicht gefunden: $config_file"
+    return 1
+  fi
+
+  node_binary="$(node -p 'process.execPath')" || return 1
+  echo "   Starting/restarting $instance_name using Node: $node_binary"
+  # PM2 retains the old script path even when restarting via a config file.
+  # Recreate only this app so legacy `script: node` entries migrate as well.
+  if pm2 describe "$instance_name" >/dev/null 2>&1; then
+    pm2 delete "$instance_name" || return 1
+  fi
+  DEPLOY_NODE_BINARY="$node_binary" pm2 start "$config_file" \
+    --only "$instance_name" --update-env
+}
+
+deploy_wait_for_http() {
+  local instance_name="$1"
+  local url="$2"
+  local attempt
+
+  echo "   Waiting for $instance_name: $url"
+  for ((attempt = 1; attempt <= 30; attempt++)); do
+    if curl --fail --silent --max-time 2 "$url" >/dev/null; then
+      echo "   ✓ HTTP-Healthcheck erfolgreich: $url"
+      return 0
+    fi
+    if [ "$attempt" -lt 30 ]; then
+      sleep 2
+    fi
+  done
+
+  echo "ERROR: $instance_name antwortet nicht erfolgreich auf $url"
+  pm2 describe "$instance_name" || true
+  pm2 logs "$instance_name" --nostream --lines 30 || true
+  return 1
+}