This allows us to introduce a platform-specific `Action` to both `iced_native`
and `iced_web` and remove the `Clipboard` from `Application::update` to maintain
purity.
Additionally, this should let us implement further actions to let users query
and modify the shell environment (e.g. window, clipboard, and more!)
Instead, we ask explicitly for it in the different `update` and `draw` methods.
This way, the runtime can derive the logical position of the cursor from
the source of truth.
