Use script setup in examples

[asvae]

Vuestic-ui version: 1.5.3

Why: makes them prettier

How important - not too much, but also pretty good long term.

setup+ / standard / TypeScript

[asvae]

@m0ksem maybe you think we don't need to use script setup in examples and instead use options api or composition api on top of options api.

[kushich]

@asvae what about some script section switch to show options api or composition api example? Would be a good thing for vue newcomers who want to see a completed example for particular api choice.

[m0ksem]

We can have both Composition API and Options API example, just need to tweak page-config compiler...