More styles/ function for progress handle api

Thank you for such a useful plugin!

I use "Non-LSP progress messages" for few custom tasks in my workspace. Right now `handle:finish()` and `handle:cancel()` both have same style and `progress.display.done_style` doesn't seem to affect the progress icon after finish/ cancel.

Can there be more functionality added to progress handle api such as?

- Indicate progress failed? (considering done is success)
- Set style for Progress done/ success (a success scenario)
- Set style for Progress failure

Start by reading the progress handle API around handle:finish() and handle:cancel(), then inspect how progress.display.done_style is applied to the progress icon. Clarify the success and failure states and their separate styles, and verify that the handle API exposes the requested behavior for non-LSP progress messages.

Written by the indexing model from the issue text.