feat: add Dockerfile for application containerization

Dockerfile

@@ -0,0 +1,20 @@
+# Build stage
+FROM node:20-alpine
+
+# Set working directory
+WORKDIR /app
+
+# Copy package files
+COPY package.json ./
+
+# Install dependencies
+RUN npm install
+
+# Copy source code
+COPY . .
+
+# Expose port
+EXPOSE 3000
+
+# Start the application
+CMD ["node", "server.js"]