type(reactivity): support distribution of union types

[yangxiuxiu1115]

fix #9903

[github-actions]

Size Report

Bundles

File	Size	Gzip	Brotli
runtime-dom.global.prod.js	87.1 kB	33.1 kB	29.9 kB
vue.global.prod.js	133 kB	50 kB	44.8 kB

Usages

Name	Size	Gzip	Brotli
createApp	48.4 kB	19 kB	17.4 kB
createSSRApp	51.6 kB	20.3 kB	18.5 kB
defineCustomElement	50.7 kB	19.8 kB	18.1 kB
overall	61.7 kB	23.9 kB	21.7 kB

[codspeed-hq]

CodSpeed Performance Report

Merging #9909 will not alter performance

_{Comparing RicardoErii:feat/setup-ref-type (fa5bf44) with main (a8d0b1b)}

Summary

✅ 53 untouched benchmarks

[yyx990803]

Looks like the previous complication was introduced in #4100, which is also fixed by having the extra distribute type, so the distribute type itself can be simplified.

I also added tests in fa5bf44

[yangxiuxiu1115]

It looks like it is, thanks