Consider only accepting render prop as children of React VList/Virtualizer

[inokawa]

Is your feature request related to a problem? Please describe.

React VList/Virtualizer accepts both elements and render props as its children. Both have trade-offs for perf explained here and it's a little confusing. Maybe we can merge them into one with a strategy like useCachedChildren of react-aria.

Describe the solution you'd like
Fix React VList/Virtualizer to accept only render prop.

If we do it, we have to take care about:

• It will disable the ability to render header/footer element as children. Probably we can do the same thing with Virtualizer and its startMargin prop. We have to check it's enough for the usecase.
• It will disable the ability to accept RSC as its children (maybe not used often though).

Describe alternatives you've considered
Accept both elements and render prop as before.

Additional context
N/A