Shortcut for removing widgets

In HTML there is a shortcut for “Unwrap/Remove...” for removing HTML tags. This would be a really useful feature for removing widgets in Flutter. Instead of using the option “Remove this widget” in the context actions dialog.

Reference to [https://youtrack.jetbrains.com/issue/IDEA-378370](https://youtrack.jetbrains.com/issue/IDEA-378370)

Start by locating the existing “Remove this widget” context action in the Flutter IntelliJ plugin and compare it with the referenced HTML “Unwrap/Remove...” shortcut. Determine how a shortcut should invoke the action, then verify that it removes Flutter widgets without requiring the context-actions dialog.

Written by the indexing model from the issue text.