chore: add root-level CLAUDE.md and docker-compose.yml

Monorepo root files for documentation and unified Docker Compose
that brings up all three services (db, api, front, intra) together.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -0,0 +1,50 @@
+services:
+  db:
+    image: postgres:16-alpine
+    restart: unless-stopped
+    environment:
+      POSTGRES_DB: nest_db
+      POSTGRES_USER: nest_user
+      POSTGRES_PASSWORD: nest_password
+    volumes:
+      - db_data:/var/lib/postgresql/data
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U nest_user -d nest_db"]
+      interval: 5s
+      timeout: 5s
+      retries: 5
+
+  api:
+    build: ./nest-backend
+    restart: unless-stopped
+    ports:
+      - "3000:3000"
+    environment:
+      DATABASE_URL: postgresql://nest_user:nest_password@db:5432/nest_db
+      JWT_SECRET: ${JWT_SECRET:-change_me_in_production}
+      PORT: 3000
+      ADMIN_USERNAME: ${ADMIN_USERNAME:-admin}
+      ADMIN_EMAIL: ${ADMIN_EMAIL:-admin@crowmate.fr}
+      ADMIN_PASSWORD: ${ADMIN_PASSWORD:-change_me}
+      FRONT_ORIGIN: ${FRONT_ORIGIN:-http://localhost:5173}
+      INTRA_ORIGIN: ${INTRA_ORIGIN:-http://localhost:5174}
+    depends_on:
+      db:
+        condition: service_healthy
+    command: >
+      sh -c "npx prisma db push && node dist/index.js"
+
+  front:
+    build: ./nest-front
+    restart: unless-stopped
+    ports:
+      - "5173:5173"
+
+  intra:
+    build: ./nest-intra
+    restart: unless-stopped
+    ports:
+      - "5174:5174"
+
+volumes:
+  db_data: