[Mac] Fixes raw keyDown/textInput handling

[Gillibald]

What does the pull request do?

This PR preserves the order of keyDown/textInput processing but still allows the current IME to consume keyDown events.

_lastKeyHandled no longer prevents keyDown events. It is now only used for some internal state.

What is the current behavior?

What is the updated/expected behavior with this PR?

How was the solution implemented (if it's not obvious)?

Checklist

• Added unit tests (if possible)?
• Added XML documentation to any related classes?
• Consider submitting a PR to https://github.com/AvaloniaUI/Documentation with user documentation

Breaking changes

Obsoletions / Deprecations

Fixed issues

Fixes: #12571

[avaloniaui-team]

You can test this PR using the following package version. 11.0.999-cibuild0039155-beta. (feed url: https://nuget-feed-all.avaloniaui.net/v3/index.json) [PRBUILDID]

[BAndysc]

I had a bug in my app after migrating to Avalonia 11 related to the event order, which was fixed by #12560. Does it mean the user code has to take into account that the order of the events might be different depending on the platform?

[avaloniaui-team]

You can test this PR using the following package version. 11.0.999-cibuild0039161-beta. (feed url: https://nuget-feed-all.avaloniaui.net/v3/index.json) [PRBUILDID]

[Gillibald]

I could find a way to preserve event order and still support consuming keyDown events by IME

Order is still:

PreviewKeyDown
KeyDown
PreviewTextInput
TextInput

[avaloniaui-team]

You can test this PR using the following package version. 11.0.999-cibuild0039165-beta. (feed url: https://nuget-feed-all.avaloniaui.net/v3/index.json) [PRBUILDID]