chore: add Dockerfile for Node.js application setup

dockerfile

@@ -0,0 +1,17 @@
+# Dockerfile for a simple Node.js app with index.js
+
+FROM node:18-alpine
+
+# set working directory
+WORKDIR /app
+
+# copy package files and install dependencies (if any)
+# if you don't have package.json you can omit these lines
+COPY package*.json ./
+RUN npm install
+
+# copy the rest of the app
+COPY . .
+
+# default command to run the app
+CMD ["node", "index.js"]