feat: ESP32 DIY platform Phase 1 — marketplace with mock payment & flash token flow

- React+Vite frontend (dark theme, role-based routing: admin/seller/buyer)
- Express+Prisma+PostgreSQL backend with JWT auth and audit logging
- MinIO object storage with backend proxy for CORS-free firmware delivery
- Mock payment flow (order → mock-pay → FlashToken) for pre-business testing
- FlashToken lifecycle: issue → validate → esp-web-tools manifest → consume
- Admin approval workflow for project/product submissions
- Toss Payments integration guide (TOSS_PAYMENT_GUIDE.md) for live keys

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

docker-compose.yml

@@ -0,0 +1,80 @@
+services:
+  platform-db:
+    image: postgres:16-alpine
+    restart: unless-stopped
+    volumes:
+      - platform-db-data:/var/lib/postgresql/data
+    environment:
+      POSTGRES_DB: platform
+      POSTGRES_USER: platform
+      POSTGRES_PASSWORD: ${DB_PASSWORD}
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U platform"]
+      interval: 10s
+      timeout: 5s
+      retries: 5
+
+  platform-redis:
+    image: redis:7-alpine
+    restart: unless-stopped
+    volumes:
+      - platform-redis-data:/data
+    command: redis-server --appendonly yes
+
+  platform-minio:
+    image: minio/minio:latest
+    restart: unless-stopped
+    volumes:
+      - platform-storage:/data
+    environment:
+      MINIO_ROOT_USER: ${MINIO_USER}
+      MINIO_ROOT_PASSWORD: ${MINIO_PASSWORD}
+    command: server /data --console-address ":9001"
+    healthcheck:
+      test: ["CMD", "mc", "ready", "local"]
+      interval: 10s
+      timeout: 5s
+      retries: 5
+
+  platform-backend:
+    build: ./backend
+    restart: unless-stopped
+    ports:
+      - "3201:3201"
+    depends_on:
+      platform-db:
+        condition: service_healthy
+      platform-redis:
+        condition: service_started
+      platform-minio:
+        condition: service_started
+    environment:
+      PORT: 3201
+      DATABASE_URL: postgresql://platform:${DB_PASSWORD}@platform-db:5432/platform
+      REDIS_URL: redis://platform-redis:6379
+      MINIO_ENDPOINT: platform-minio
+      MINIO_PORT: "9000"
+      MINIO_ACCESS_KEY: ${MINIO_USER}
+      MINIO_SECRET_KEY: ${MINIO_PASSWORD}
+      MINIO_BUCKET: platform
+      MINIO_USE_SSL: "false"
+      JWT_SECRET: ${JWT_SECRET}
+      JWT_EXPIRES_IN: 7d
+      TOSS_CLIENT_KEY: ${TOSS_CLIENT_KEY:-test_ck_placeholder}
+      TOSS_SECRET_KEY: ${TOSS_SECRET_KEY:-test_sk_placeholder}
+      BASE_URL: ${BASE_URL:-http://localhost:3200}
+      WEBFLASH_INTERNAL_TOKEN: ${WEBFLASH_INTERNAL_TOKEN}
+      NODE_ENV: production
+
+  platform-frontend:
+    build: ./frontend
+    restart: unless-stopped
+    ports:
+      - "3200:80"
+    depends_on:
+      - platform-backend
+
+volumes:
+  platform-db-data:
+  platform-redis-data:
+  platform-storage: