Function resolveBuiltin

resolveBuiltin(
builtins: readonly BuiltinApplet[],
id: string,
): Promise<ResolvedApplet>
Load an applet that comes with the shell and check it against its pinned hash.

Nothing is fetched from the network and no signature is checked: the host that lists the applet is the page the user already trusts with everything else, so what it pins is as trusted as its own code. The check is that the bytes loaded are the bytes pinned. The summary is shaped like a published applet's, so grants, intents and the mount plan treat it the same.
Parameters
- builtins: readonly BuiltinApplet[]
  The applets the host ships.
- id: string
  The name from a kernl:<id> address.
Returns Promise<ResolvedApplet>
The summary and the verified index.html.
Throws
invalid:pointer for a name the host does not ship, unavailable:blob when the artifact cannot be loaded, invalid:artifact-hash when it does not match its pin.
Example
```
const { summary, indexHtml } = await resolveBuiltin(builtins, 'messages');
summary.address; // 'kernl:messages'
```