Move hardcoded Metabase credentials to Nuxt runtime config to allow configuration via environment variables and follow security best practices. Changes: - Update server/utils/metabase.ts to use useRuntimeConfig() - Add metabase config to nuxt.config.ts runtimeConfig - Update .env.example with Metabase configuration template Environment variables: - METABASE_URL (default: https://metabase.nucleoriofrio.com) - METABASE_EMAIL (required for authentication) - METABASE_PASSWORD (required for authentication)