refactor: update van_jsx

[cqh963852]

relate issue https://github.com/vanjs-org/van/issues/233

• move jsx function to createElement file
• add setAttribute function
• use onClick like instead onclick while use JSX tag
• update children type to VanNode
• add OrVanAttribute, make tag can accept (()=>T) | State<T> type

@Tao-VanJS PTAL

[Tao-VanJS]

Thanks a lot for the contribution!