Auto fix of import without extension

`Node.js` doesn’t supports imports without file extension:

```js
import client from './client';
```

This will be error, extension should be provided:

```js
import client from './client.js';
```

Extensions can be:
- `js`
- `mjs`
- `cjs`

And need to be resolved, checking what kind of a file exists.

In `CommonJS` was no such a problem, we can avoid extension:

```js
const client = require(‘./client’);
```

Because of autoresolver.

So what I want to ask is: **Is it possible to autofix cases when extension is missing?**

So there was no need to `fix` such things by hand.

That would be amazing :)!

The issue names no files, tests, or entry points. Start by locating the import-extension validation rule and its resolver, then determine how existing autofixes handle filesystem resolution; done means missing .js, .mjs, and .cjs extensions are safely resolved and autofixed without changing valid imports.

Written by the indexing model from the issue text.