feat: add ESP32 DIY platform Phase 1 (marketplace scaffold)

- Docker Compose with Postgres, Redis, MinIO, backend, frontend (port 3200/3201)
- Prisma schema: User, Project, ProjectFile, Product, Order, FlashToken, Review, AuditLog
- Backend: JWT auth, project CRUD + file upload (MinIO + sharp WebP), admin approval flow
- Frontend: React + Vite SPA with auth, project/shop browse, seller dashboard, admin panel
- Admin: pending approval queue, user management, audit log viewer, stats dashboard
- Audit logging middleware for legal compliance
- Admin init script: createAdmin.js
- Full design document in PLATFORM_DESIGN.md

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

platform/.env.example

@@ -0,0 +1,19 @@
+# PostgreSQL
+DB_PASSWORD=change_this_strong_password
+
+# MinIO (로컬 S3 스토리지)
+MINIO_USER=minioadmin
+MINIO_PASSWORD=change_this_strong_password
+
+# JWT (openssl rand -hex 64 로 생성 권장)
+JWT_SECRET=change_this_very_long_random_secret_string
+
+# 배포 URL (DNS 설정 후 변경)
+BASE_URL=http://localhost:3200
+
+# 토스페이먼츠 (https://developers.tosspayments.com 에서 발급)
+TOSS_CLIENT_KEY=test_ck_YOUR_KEY
+TOSS_SECRET_KEY=test_sk_YOUR_KEY
+
+# webflash 연동 내부 토큰 (임의 UUID)
+WEBFLASH_INTERNAL_TOKEN=change_this_token