Move client and server dockerfile to special path

docker/Dockerfile.server

@@ -0,0 +1,13 @@
+FROM node:20-alpine
+
+WORKDIR /app
+
+COPY package*.json ./
+RUN npm ci --omit=dev
+
+COPY server ./server
+
+ENV NODE_ENV=production
+EXPOSE 3000
+
+CMD ["npm", "start"]