/**
 * `true` when running under a production bundle.
 *
 * Webpack's DefinePlugin and Vite's `define` replace the literal expression
 * `process.env.NODE_ENV` at build time. We reference it directly (rather
 * than via `globalThis`) so that replacement actually fires. The
 * `typeof process !== 'undefined'` guard makes raw-browser execution
 * (no polyfill, no bundler) safe.
 */
export declare function isProductionEnv(): boolean;