refactor: migrate to Composition API with SFC Setup and new defaults

[ShGKme]

Follow 2022+ Vue recommendations and defaults:

• Migrate to Composition API
  • Using SFC Setup as a new default recommendation and a place with better TS support with new features in Vue 3
• Change block order to script, template
  • Places template close to styles

Add corresponding ESLint rules

[Antreesy]

Apart from it, migrated 1:1

[Antreesy]

Not needed here anymore?

For myself: https://github.com/vuejs/rfcs/blob/master/active-rfcs/0040-script-setup.md#declaring-additional-options

[ShGKme]

It was here by mistake. Added a "long" time ago, then Help was implemented as a NcModal wrapper.

In SFC Setup it's easy to add it via

defineOptions({
  inheritAttrs: false,
})

But in Vue 2 it is not available and requires an additional block:

<script>
export default {
  inheritAttrs: false, 
}
</script>