Suggestion: Standard Schema support for `.json()`

Similar to https://github.com/dsherret/path/issues/22, it would be useful if `$``.json()` and `$.request().json()` allowed you to pass in a [Standard Schema](https://standardschema.dev/schema) to easily validate the JSON:

```ts
import * as v from "valibot";

const OutputSchema = v.object({ prop: v.number() });
// const { prop } = v.parse(OutputSchema, await $`echo '{ "prop": 5 }'`.json());
const { prop } = await $`echo '{ "prop": 5 }'`.json(OutputSchema);

const DPrintPlugins = v.object({
schemaVersion: v.literal(4),
latest: v.array(v.object({
// ...
})),
});
// const data = v.parse(DPrintPlugins, await $.request("https://plugins.dprint.dev/info.json").json());
const data = await $.request("https://plugins.dprint.dev/info.json").json(DPrintPlugins);
```

(This idea is [inspired by Ky](https://github.com/sindresorhus/ky/blob/3419113b48e034fdcf8fa6bd3be3da7b3d0d758f/readme.md?plain=1#L155))

Start by locating the public `.json()` entry points for shell commands and `$.request().json()`, then read how their current JSON results are typed and returned. Add support for accepting a Standard Schema as shown in the issue, and verify that the parsed result is validated and typed for both usage patterns.

Written by the indexing model from the issue text.