feat: add docker build

Dockerfile

@@ -0,0 +1,21 @@
+FROM node:20-alpine AS build
+WORKDIR /app
+
+RUN npm install -g pnpm
+COPY package.json pnpm-lock.yaml ./
+RUN pnpm install --frozen-lockfile
+
+COPY . .
+RUN pnpm run build
+RUN pnpm prune --prod
+
+FROM node:20-alpine
+WORKDIR /app
+COPY --from=build /app/build /app
+COPY --from=build /app/node_modules /app/node_modules
+RUN echo '{"type":"module"}' > /app/package.json
+
+EXPOSE 3000
+ENV NODE_ENV=production
+ENV HOST=0.0.0.0
+CMD [ "node_modules/.bin/remix-serve", "server/index.js" ]