types(defineComponent): Keep slot information on functional components

[pikax]

fix https://github.com/vuejs/core/issues/9649

Appends slot information as props, since the SlotType relies on a symbol, that won't bleed out to props.

I personally don't really like this approach, since I would preferably align this to typescript Slot support, Vue language tools will need to be updated to expect slots in props.

[github-actions[bot]]

Size Report

Bundles

File	Size	Gzip	Brotli
runtime-dom.global.prod.js	86.7 kB	33 kB	29.8 kB
vue.global.prod.js	133 kB	49.8 kB	44.6 kB

Usages

Name	Size	Gzip	Brotli
createApp	48.2 kB	19 kB	17.4 kB
createSSRApp	51.5 kB	20.3 kB	18.5 kB
defineCustomElement	50.6 kB	19.7 kB	18 kB
overall	61.6 kB	23.8 kB	21.7 kB

[TylerAPfledderer]

Hi @pikax! Interested in knowing any update with this PR? 😄

[bee1an]

Hi @pikax looking forward to your fixing this