Updated README.md

[d-dovale]

• Added clearer overview and main features section
• Improved readability with better structure and table of contents
• Enhanced examples with AJAX handling and Page Object Model
• Clarified installation steps for both pre-release and stable versions
• Updated migration guide for users transitioning between versions

[yashaka]

Oh! Thank you for the PR. Looks as an update in a good direction. Let me review it deeply!

[yashaka]

I have just started the review. I am doing it locally, tuning it along the way:) Hope to finish it till the end of next week. Let's see how fast I can be. Sorry for the delay...

[yashaka]

I will remove the widget example for now... Probably it would be better to add a separate guide in docs for that, provide more examples of widgets, probably more complicated ones, like the ones for DatePickers, or DataGrid components, and just leave the link in the README...