Rule proposal: `prefer-script-setup`

[cexbrayat]

Please describe what the rule should do:

As script setup is slowing becoming the recommended way to declare a component, it would be nice to have a rule that checks the components of a project and warn the author if a component does not use script setup

What category should the rule belong to?

[ ] Enforces code style (layout)
[ ] Warns about a potential error (problem)
[x] Suggests an alternate way of doing something (suggestion)
[ ] Other (please specify:)

Provide 2-3 code examples that this rule should warn about:

<script lang="ts">
import { defineComponent } from 'vue';
export default defineComponent({
 //...
});
</script>

This should not warn:

<script setup lang="ts">
</script>

[ota-meshi]

Thank you for the rule proposal! Sounds good to me!
However, I think some users may prefer the plain Composition API or Options API.
Do you think the rule should have options to work for these users as well?

[cexbrayat]

That's a good point. Maybe it's a good idea to have options for this. As Composition API seems to be what should be favored, that could be the default?