UserFeedback Widget improvements

[buenaflor]

Description

See Flutter section: getsentry/team-mobile#205

• Widget customization options, see Android impl as as inspiration
• Show Screenshot in Widget
• Choosing Screenshot like in React Native (widget hides and user can then go to any screen they like and take a screenshot and then the widget opens again)
• Docs (see Android)

[ueman]

Surely, you want to take over https://pub.dev/packages/feedback for the annotation feature, right? 😆

[buenaflor]

I'm not opposed to it :)

are you not actively maintaining it anymore?

[ueman]

I fix stuff that's otherwise breaking, but I don't have a use for it myself, so it's hard to justify all the time spent on it