export default

## Feature Request

Great work :+1:

## Overview

It would be nice to export default functions.

## **Example:**

```js
export function decrement(): i32 {}
export function increment(): i32 {}

export default {
decrement,
increment,
};
```

The issue names no files, tests, or entry points and provides only a JavaScript-like example. Start by tracing how export declarations and module exports are handled, then define the expected behavior for the shown default object; done means the example compiles and exposes decrement and increment through the default export.

Written by the indexing model from the issue text.