Constant folding failure

```js
const a = 256 * 2;
```
minify to
```js
const a=512;
```
(https://esbuild.github.io/try/#dAAwLjI1LjgALS1taW5pZnkAY29uc3QgYSA9IDI1NiAqIDI7)

But
```js
0;
const a = 256 * 2;
```
minify to
```js
const a=256*2;
```
(https://esbuild.github.io/try/#dAAwLjI1LjgALS1taW5pZnkAMDsKY29uc3QgYSA9IDI1NiAqIDI7), where constant folding fails.

Start with the two esbuild Try links and compare the minified output for the snippets with and without the leading `0;`. Trace constant-folding and statement-removal behavior in the minifier, then add or run a regression case showing that `256 * 2` becomes `512` in both contexts.

Written by the indexing model from the issue text.