The closure passed to `eframe::run_native` now returns a `Result`,
allowing you to return an error during app creation, which will be
returned to the caller of `run_native`.
This means you need to wrap your `Box::new(MyApp::new(…))` in an
`Ok(…)`.
* Closes https://github.com/emilk/egui/issues/4474
# What's New
* eframe: Added `App::raw_input_hook` allows for the manipulation or
filtering of raw input events
A filter applied to raw input before [`Self::update`]
This allows for the manipulation or filtering of input events before
they are processed by egui.
This can be used to exclude specific keyboard shortcuts, mouse events,
etc.
Additionally, it can be used to add custom keyboard or mouse events
generated by a virtual keyboard.
* examples: Added an example to demonstrates how to implement a custom
virtual keyboard.
[eframe-custom-keypad.webm](https://github.com/emilk/egui/assets/1274171/a9dc8e34-2c35-4172-b7ef-41010b794fb8)
