chore: add user for the smithery dockerfile (#458)

Author: nirinchev

.smithery/Dockerfile

@@ -1,6 +1,10 @@
 # Generated by https://smithery.ai. See: https://smithery.ai/docs/config#dockerfile
 # ----- Build Stage -----
 FROM node:lts-alpine AS builder
+
+RUN adduser -D mcpuser
+USER mcpuser
+
 WORKDIR /app
 
 # Copy package and configuration