- Zod-based baseEnvSchema (PORT, HOST, NODE_ENV, CORS_ORIGIN, SERVICE_NAME, COSMOS_*)
- loadConfig() with extension support for service-specific fields
- loadProductIdentity() reads product.json or falls back to env vars
- getProductId() convenience function
- Replaces 5 duplicated product-config.ts files across LysnrAI
- Peer dep: zod >=3.20.0
