Declare global `window` interface

any-other-file.ts

// Usage example
import './global.types.ts';

// Enough to be imported in a single file, closer to the app's initialisation.

global.types.ts

// some internal types
import { EnvConfig } from '@/some/internal/type/for/env';

declare global {
  interface Window {
    env: EnvConfig;
  }
}

// needed to make the file exportable
export {};