many changes in the architecture

Author: dineshsuthar123

.env.example

@@ -1,21 +1,18 @@
-# ===================================
-# SupplyChain-Auth Environment Template
-# Copy to `.env` and replace placeholder values locally
-# ===================================
+# Rename this file to .env and replace the placeholder values before running the stack
 
+# ===================================
 # Application Environment
+# ===================================
 NODE_ENV=development
 REACT_APP_ENV=development
 
-# ===================================
-# API Configuration
-# ===================================
+# Frontend API Base URLs (for development)
 REACT_APP_API_BASE_URL=http://localhost:8080
 REACT_APP_API_PRODUCTS_URL=http://localhost:8080/api/products
 REACT_APP_API_VERIFICATION_URL=http://localhost:8080/api/verify
 REACT_APP_API_EVENTS_URL=http://localhost:8080/api/events
 
-# Backend Service URLs
+# Backend Service URLs (used by frontend or gateway)
 PRODUCT_SERVICE_URL=http://localhost:8081
 VERIFICATION_SERVICE_URL=http://localhost:8082
 EVENT_SERVICE_URL=http://localhost:8083
@@ -25,38 +22,41 @@ EVENT_SERVICE_URL=http://localhost:8083
 # ===================================
 MONGODB_URI=mongodb://localhost:27017/supplychain_auth
 MONGODB_DATABASE=supplychain_auth
-MONGODB_USERNAME=<mongo_username>
-MONGODB_PASSWORD=<mongo_password>
+MONGODB_USERNAME=change_me_mongo_user
+MONGODB_PASSWORD=change_me_mongo_password
 
 REDIS_URL=redis://localhost:6379
-REDIS_PASSWORD=<redis_password>
+# Wrap passwords containing $ or ! in double quotes to avoid Docker variable expansion
+REDIS_PASSWORD="change_me_redis_password"
 
 POSTGRES_URL=postgresql://localhost:5432/supplychain_auth
-POSTGRES_USERNAME=<postgres_username>
-POSTGRES_PASSWORD=<postgres_password>
+POSTGRES_DB=supplychain_auth
+POSTGRES_USERNAME=change_me_pg_user
+POSTGRES_PASSWORD=change_me_pg_password
 
 # ===================================
-# Blockchain Configuration (Free Testnet)
+# Blockchain Configuration
 # ===================================
 BLOCKCHAIN_NETWORK=sepolia
-ETHEREUM_RPC_URL=https://sepolia.infura.io/v3/<infura_project_id>
-PRIVATE_KEY=<private_key_for_testnet>
-CONTRACT_ADDRESS=<deployed_contract_address>
+ETHEREUM_RPC_URL=https://sepolia.infura.io/v3/<your_project_id>
+PRIVATE_KEY=0xYOUR_PRIVATE_KEY
+CONTRACT_ADDRESS=0xYourContractAddress
+NFT_CONTRACT_ADDRESS=0xYourNftContract # optional, defaults to zero address during deploy
+ZK_VERIFIER_ADDRESS=0xYourZkVerifier  # optional, defaults to zero address during deploy
 
 # ===================================
 # Security Configuration
 # ===================================
-JWT_SECRET=<generate_strong_jwt_secret>
+JWT_SECRET=change_me_jwt_secret
 JWT_EXPIRES_IN=24h
 JWT_REFRESH_EXPIRES_IN=7d
-ENCRYPTION_KEY=<32_byte_hex_key>
+ENCRYPTION_KEY=64_char_hex_string_value_here
 
 # ===================================
-# External Services (Free Tiers)
+# External Services
 # ===================================
-EMAIL_SERVICE_API_KEY=<mailgun_api_key>
-EMAIL_FROM=<noreply@example.com>
-
+EMAIL_SERVICE_API_KEY=your_mail_service_api_key
+EMAIL_FROM=noreply@example.com
 STORAGE_TYPE=local
 STORAGE_PATH=./uploads
 
@@ -72,21 +72,9 @@ METRICS_PORT=9090
 # ===================================
 PORT=8080
 HOST=localhost
-CORS_ORIGINS=http://localhost:3000,https://your-app.vercel.app
+CORS_ORIGINS=http://localhost:3000
 RATE_LIMIT_WINDOW_MS=900000
 RATE_LIMIT_MAX_REQUESTS=100
-
-# ===================================
-# Development Settings
-# ===================================
 DEBUG_MODE=true
 ENABLE_SWAGGER=true
 CHOKIDAR_USEPOLLING=true
-
-# ===================================
-# Production Overrides (set via deployment env)
-# ===================================
-# REACT_APP_API_BASE_URL=https://your-backend.example.com
-# MONGODB_URI=<production_mongodb_connection>
-# REDIS_URL=<production_redis_connection>
-# JWT_SECRET=<production_jwt_secret>