support HTML event registration via the page instance

[hyyan]

webforj/webforj#686

[MatthewHawkins]

Brief outline in the release blog, can be used to expand into a more comprehensive section/article:

https://docs.webforj.com/blog/whats-new-v24.11#using-the-page-for-html-event-registration

[MatthewHawkins]

Add to this section for now:

https://docs.webforj.com/docs/building-ui/events