chore: 提交前后端dockerfile

apps/backend/Dockerfile

@@ -0,0 +1,19 @@
+FROM node:22-alpine AS builder
+RUN npm install -g pnpm
+WORKDIR /app
+COPY package.json pnpm-lock.yaml ./
+RUN pnpm install --frozen-lockfile --prod
+COPY . .
+
+RUN pnpm run build
+
+FROM node:22-alpine
+RUN npm install -g pnpm
+WORKDIR /app
+COPY package.json pnpm-lock.yaml ./
+RUN pnpm install --frozen-lockfile --prod
+COPY --from=builder /app/dist ./dist
+COPY --from=builder /app/node_modules ./node_modules
+
+EXPOSE 3001
+CMD ["pnpm", "run", "start:prod"]