Use raw input instead of WM messages to detect physical key events

Description

It seems that currently Winit on Windows relies entirely on window messages to detect key down/up events for its own event loop that dispatches WindowEvent::KeyboardInput.

However, this detection fails in some cases. For example (✓ marks winit correctly processing/dispatching physical key event, ✗ fails):

1. ✓ ↓LeftShift
2. ✓ ↓RightShift (although it's marked as "repeat", but that might be a different bug (already mentioned) or maybe the cause is the same)
3. X ↑RightShift
4. ✓ ↑LeftShift

Searching around this is identical to https://github.com/SFML/SFML/issues/1301, and the solution there was to use raw input events https://github.com/SFML/SFML/pull/1449/files

Brief testing by printing raw input events in handle_raw_input shows that yes, the 3rd ↑RightShift event IS detected with raw input even though it's hidden in the current WindowEvent::KeyboardInput

So maybe Winit should switch to RawInput comletely for physical keys? Since it also has the legacy WM_KEYDOWN/up messages, you wouldn't lose any information to construct Winit events? https://learn.microsoft.com/en-us/windows/win32/api/winuser/ns-winuser-rawkeyboard

(note: this is about physical key events, not logical modifier state)

Windows version

Microsoft Windows [Version 10.0.26100.4061]

Winit version

git using this sample app (cargo run --example window)

Start with the Windows handle_raw_input path and the linked sample app, running cargo run --example window to reproduce the missing RightShift release. Compare raw input with the current keyboard event handling and consult the linked raw keyboard API reference. Done means physical key events, including the reported RightShift release, are dispatched reliably.