Use type assertion when no variable binding is around

[rikukissa]

So instead of using a generic type variable in the typehole, the plugin could add

import App from "./App.svelte";
import typehole from "typehole";

type AutoDiscovered = any;

const app = new App({
  target: typehole.t<AutoDiscovered>(document.getElementById("app")),
});

export default app;

import App from "./App.svelte";
import typehole from "typehole";

type AutoDiscovered = any;

const app = new App({
  target: typehole.t(document.getElementById("app") as AutoDiscovered),
});

export default app;