Every component resolves its defaults through a configuration cascade, and the provider is where that
cascade starts. It takes one `config` object, resolves it once, and gives every component below it the
values it should use. It also paints the palette: the web writes the `--ashee-*` custom properties, the
device follows the platform's colour scheme and applies the same values to its styles.

One provider belongs at each application's root, above the router's outlet on the web and inside the
safe-area provider on a device.

```tsx
import { AsheeUIProvider } from "asheeui";

export function Root({ children }) {
  return (
    <AsheeUIProvider config={{ defaultTheme: "system", defaultRadius: "sm" }}>
      {children}
    </AsheeUIProvider>
  );
}
```

## The same type on both branches

`AsheeConfig` is the umbrella's name for the configuration type: the web branch aliases
`ExternalConfig`, the native branch accepts the same object plus its platform-only fields. A shared
file can export the object and both applications pass it without a cast.

## A component outside the provider

Rendering one outside throws rather than falling back to a silent default. A missing provider is a
setup mistake, and a default would hide it until a screen looked subtly wrong in production.

## Props

```props AsheeUIProvider
```