docs: 저장소 소개를 ARA SYSTEM 의 지금 구성에 맞게 고치고 로드맵을 더한다

루트 README · CLAUDE.md · 점검 목록이 아직 "풀스택 모노레포 템플릿"으로 소개하고 있었다 — 사내 그룹웨어(메일 운영 중)에 맞게
지금 상태 · 구성(메일 엔진 · 리졸버 · ClamAV · 운영 스크립트 포함) · 문서 지도 · 디렉터리 구조로 다시 쓰고,
백엔드를 호스트에서 npm ci 하라던 옛 안내(컨테이너 안에서만 — 규칙과 반대)를 뺐다.
docs/roadmap.md 에 메일 1~16단계 상태(16단계 첫 항목: 주소록 가져오기 · 내보내기) · 공통 기반 · 2부 · 앱 · 추후 후보 모음을 둔다.
backend · frontend README 는 프레임워크가 만든 영어 안내 대신 이 저장소의 실행 · 검사 · 참고 문서로,
규칙 · 스킬 · 역할 문서의 "템플릿" 표현("템플릿 기본 제공 골격" 등)은 "기본 골격"으로 바꿨다(nginx 설정 템플릿은 그대로).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

backend/README.md

@@ -1,98 +1,36 @@
-<p align="center">
-  <a href="http://nestjs.com/" target="blank"><img src="https://nestjs.com/img/logo-small.svg" width="120" alt="Nest Logo" /></a>
-</p>
+# backend — ARA SYSTEM API (NestJS)
 
-[circleci-image]: https://img.shields.io/circleci/build/github/nestjs/nest/master?token=abc123def456
-[circleci-url]: https://circleci.com/gh/nestjs/nest
+웹 · 앱이 함께 쓰는 REST API 다(`/api`). 메일 엔진(Stalwart)을 JMAP 으로 감싸고, 로그인 세션 · 설정 · 검색 색인 · 앱 알림 · 대용량 첨부 · 운영 도구를 맡는다.
 
-  <p align="center">A progressive <a href="http://nodejs.org" target="_blank">Node.js</a> framework for building efficient and scalable server-side applications.</p>
-    <p align="center">
-<a href="https://www.npmjs.com/~nestjscore" target="_blank"><img src="https://img.shields.io/npm/v/@nestjs/core.svg" alt="NPM Version" /></a>
-<a href="https://www.npmjs.com/~nestjscore" target="_blank"><img src="https://img.shields.io/npm/l/@nestjs/core.svg" alt="Package License" /></a>
-<a href="https://www.npmjs.com/~nestjscore" target="_blank"><img src="https://img.shields.io/npm/dm/@nestjs/common.svg" alt="NPM Downloads" /></a>
-<a href="https://circleci.com/gh/nestjs/nest" target="_blank"><img src="https://img.shields.io/circleci/build/github/nestjs/nest/master" alt="CircleCI" /></a>
-<a href="https://discord.gg/G7Qnnhy" target="_blank"><img src="https://img.shields.io/badge/discord-online-brightgreen.svg" alt="Discord"/></a>
-<a href="https://opencollective.com/nest#backer" target="_blank"><img src="https://opencollective.com/nest/backers/badge.svg" alt="Backers on Open Collective" /></a>
-<a href="https://opencollective.com/nest#sponsor" target="_blank"><img src="https://opencollective.com/nest/sponsors/badge.svg" alt="Sponsors on Open Collective" /></a>
-  <a href="https://paypal.me/kamilmysliwiec" target="_blank"><img src="https://img.shields.io/badge/Donate-PayPal-ff3f59.svg" alt="Donate us"/></a>
-    <a href="https://opencollective.com/nest#sponsor"  target="_blank"><img src="https://img.shields.io/badge/Support%20us-Open%20Collective-41B883.svg" alt="Support us"></a>
-  <a href="https://twitter.com/nestframework" target="_blank"><img src="https://img.shields.io/twitter/follow/nestframework.svg?style=social&label=Follow" alt="Follow us on Twitter"></a>
-</p>
-  <!--[![Backers on Open Collective](https://opencollective.com/nest/backers/badge.svg)](https://opencollective.com/nest#backer)
-  [![Sponsors on Open Collective](https://opencollective.com/nest/sponsors/badge.svg)](https://opencollective.com/nest#sponsor)-->
+- 모듈 지도 · 개발 규칙: [`.claude/skills/nestjs/SKILL.md`](../.claude/skills/nestjs/SKILL.md)
+- API 약속(웹 · 앱과 함께): [`docs/mail/api-contract.md`](../docs/mail/api-contract.md)
+- 공통 규칙(응답 꼴 · 에러 코드 · 로그 · 보안): [`CLAUDE.md`](../CLAUDE.md)
 
-## Description
+## 실행 — 컨테이너로
 
-[Nest](https://github.com/nestjs/nest) framework TypeScript starter repository.
-
-## Project setup
+백엔드는 늘 컨테이너로 띄운다. 의존성 · lock 이 Linux 기준이라 **호스트에서 `npm install` 하지 않는다**(바꿀 때도 컨테이너 안에서 — nestjs 스킬 "의존성 추가/제거").
 
 ```bash
-$ npm install
+# 저장소 루트에서 — 개발 스택(backend + db + 메일 엔진)
+docker compose -f docker-compose.yml -f docker-compose.dev.yml --env-file .env.development up -d
+docker compose -f docker-compose.yml -f docker-compose.dev.yml --env-file .env.development logs -f backend
 ```
 
-## Compile and run the project
+- 처음 띄우면 마이그레이션을 한 번 돌리고 watch 빌드를 시작한다(Windows 바인드 마운트라 수십 분 걸릴 수 있다). 코드를 고치면 저절로 다시 뜬다.
+- Swagger: <http://localhost:3000/api-docs>
+
+## 시험 · 검사
 
 ```bash
-# development
-$ npm run start
-
-# watch mode
-$ npm run start:dev
-
-# production mode
-$ npm run start:prod
+docker exec arasystem-backend npm run lint                             # 경고 0
+docker exec arasystem-backend npm run test                             # 단위 — 메모리가 빠듯하면 -- --maxWorkers=2
+docker exec arasystem-backend npx jest --config ./test/jest-e2e.json   # e2e — DB · 메일 엔진 필요
 ```
 
-## Run tests
+컨테이너 이름은 `<PROJECT_NAME>-backend`(개발 기본 `arasystem`). Git Bash 에서 컨테이너 안 경로를 줄 때는 `MSYS_NO_PATHCONV=1` 을 붙인다.
 
-```bash
-# unit tests
-$ npm run test
+## 자주 하는 일
 
-# e2e tests
-$ npm run test:e2e
-
-# test coverage
-$ npm run test:cov
-```
-
-## Deployment
-
-When you're ready to deploy your NestJS application to production, there are some key steps you can take to ensure it runs as efficiently as possible. Check out the [deployment documentation](https://docs.nestjs.com/deployment) for more information.
-
-If you are looking for a cloud-based platform to deploy your NestJS application, check out [Mau](https://mau.nestjs.com), our official platform for deploying NestJS applications on AWS. Mau makes deployment straightforward and fast, requiring just a few simple steps:
-
-```bash
-$ npm install -g @nestjs/mau
-$ mau deploy
-```
-
-With Mau, you can deploy your application in just a few clicks, allowing you to focus on building features rather than managing infrastructure.
-
-## Resources
-
-Check out a few resources that may come in handy when working with NestJS:
-
-- Visit the [NestJS Documentation](https://docs.nestjs.com) to learn more about the framework.
-- For questions and support, please visit our [Discord channel](https://discord.gg/G7Qnnhy).
-- To dive deeper and get more hands-on experience, check out our official video [courses](https://courses.nestjs.com/).
-- Deploy your application to AWS with the help of [NestJS Mau](https://mau.nestjs.com) in just a few clicks.
-- Visualize your application graph and interact with the NestJS application in real-time using [NestJS Devtools](https://devtools.nestjs.com).
-- Need help with your project (part-time to full-time)? Check out our official [enterprise support](https://enterprise.nestjs.com).
-- To stay in the loop and get updates, follow us on [X](https://x.com/nestframework) and [LinkedIn](https://linkedin.com/company/nestjs).
-- Looking for a job, or have a job to offer? Check out our official [Jobs board](https://jobs.nestjs.com).
-
-## Support
-
-Nest is an MIT-licensed open source project. It can grow thanks to the sponsors and support by the amazing backers. If you'd like to join them, please [read more here](https://docs.nestjs.com/support).
-
-## Stay in touch
-
-- Author - [Kamil Myśliwiec](https://twitter.com/kammysliwiec)
-- Website - [https://nestjs.com](https://nestjs.com/)
-- Twitter - [@nestframework](https://twitter.com/nestframework)
-
-## License
-
-Nest is [MIT licensed](https://github.com/nestjs/nest/blob/master/LICENSE).
+- **에러 코드**: `src/common/errors/error-codes.ts` 만 고치고 호스트에서 `cd backend && npm run sync:error-codes`(웹 · 앱 사전이 함께 바뀐다).
+- **DB 스키마**: 엔티티를 고친 뒤 `docker exec arasystem-backend npm run migration:generate -- src/migrations/<이름>` → 만든 SQL 을 눈으로 확인 → 엔티티와 함께 커밋(nestjs 스킬 "DB 마이그레이션").
+- **운영 도구**(운영 서버 안 명령 — 입사 · 비밀번호 재설정 · 휴대폰 앱 올리기 등): `sudo docker exec -it <PROJECT_NAME>-backend node dist/cli/ops.js` — 계약 6절 · mail/README.