This reverts commit f5d003d1.

We decided to postpone this change until a later release, in maybe a
different shape.

API Review: Remove SharedImageBuffer from public API and rename Window::grab_window() to take_snapshot()

Use SharedPixelBuffer as return value for take_snapshot() and provide counter-parts to from_rgb* in Image as to_rgb*

When stopping a timer, the removal from the timer list requires a mutable borrow.
If during that borrow the timer's closure is dropped and a `Drop` impl starts another time, then the attempt of
acquiring a mutable borrow for the timers list to insert the new timer fails.

This change exposes functionality of already existing internal API
that all renderers use to obtain pixels for upload to the screen - so
it's rather well tested.

This also exposes the `SharedImageBuffer` API, an enum that represents
different SharedPixelBuffer encodings.

This makes it possible to use component libraries with C++.

Base the commercial license on the Royalty-free license adding clauses pertaining to the fees.

Add clarification that Application may not expose Slint APIs.

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Co-authored-by: Simon Hausmann <simon.hausmann@slint.dev>

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Co-authored-by: Simon Hausmann <simon.hausmann@slint.dev>

The android-activity 0.5 no longer works with Rust 1.78 because it
asserts with
> slice::from_raw_parts requires the pointer to be aligned and non-null, and the total size of the slice not to exceed `isize::MAX`

Note that the documentation is build with the 05 feature because it also
build the winit backend crate in the same command that still depends on
android-activity 0.5 via winit

This is the counter-part, which removes focus from the element if it's currently focused. The window - if focused - may still be focused towards the windowing system.