Wrong variable name in block scope

The following code

```js
const pts = [];
{
const pts = [];
pts.push(...[1,2,3]);
}
```
will be transformed into

```js
var pts = [];
{
var pts$1 = [];
pts$1.push.apply(pts, [1,2,3]);
}
```

The first argument of apply is wrong. It should be `pts$1.push.apply(pts$1, [1,2,3]);`

Start by reproducing the JavaScript example from the issue and inspect the transformation that renames block-scoped variables and lowers the spread call to apply. Trace why the generated receiver remains pts instead of pts$1. Done means the transformed call uses pts$1 as both the method receiver and apply context, with a regression test covering this example.

Written by the indexing model from the issue text.