Add Dockerfile for backend and frontend

Dockerfile.backend

@@ -0,0 +1,13 @@
+FROM node:18-alpine
+
+WORKDIR /app/backend
+
+COPY backend/package*.json ./
+
+RUN npm install --production
+
+COPY backend/ .
+
+EXPOSE 3000
+
+CMD ["npm", "start"]

Dockerfile.frontend

@@ -0,0 +1,15 @@
+FROM node:18-alpine
+
+WORKDIR /app/frontend
+
+COPY frontend/package*.json ./
+
+RUN npm install
+
+COPY frontend/ .
+
+RUN npm run build
+
+EXPOSE 4173
+
+CMD ["npm", "run", "preview"]