fix(wayland): restore focus during window resize

[Kkaiwz]

On Wayland, when the user resizes a window, the compositor takes over input handling. This causes GLFW to receive a keyboardHandleLeave event, which it incorrectly interprets as the window losing focus. This will result in Platform::update() no longer executed, then the render result is incorrect.

This patch forces focus to be restored in the window size callback on Wayland, ensuring that rendering continues during resize operations.

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