props inference for lang="js"

[danielroe]

Currently a component with the following script:

<script setup>
const props = defineProps({
  appName: {
    type: String,
    default: "Nuxt"
  },
})
</script>

when used in a template will give the following ts error:

Type '{}' is missing the following properties from type 'Readonly<ExtractPropTypes<{ appName: { type: StringConstructor; default: string; }; }>>': appName. ts(2322)

See nuxt/nuxt#14081