Improve error message for invalid prompt elements

[rebornix]

While crafting the prompt in tsx, sometimes I make mistakes with the element types (which are valid in tsx itself unfortunately), I got error message as

Invalid ChatMessage child! Child must be a TSX component that extends PromptElement

To troubleshoot this I would have to

• Put try catch around renderPrompt and enable Caught/uncaught Exceptions
• Traverse through the invalid element's ancestors to figure out which element it is

We could in the error message point to the problematic child (e.g. -> -> child #2)

@connor4312's suggestion can help a lot already.