[Rust] Upcoming retirement of gtk3-rs, gtk-rs-core v0.18, and gtk4-rs v0.7

[Fabio Valentini]

Hi all,

I am planning to implement this Fedora 43 Change in one week (on Aug 20, 2025):
https://fedoraproject.org/wiki/Changes/Retire_gtk3-rs,_gtk-rs-core_v0.18,_an...

The packages in the Change document will be retired in both rawhide
and f43 branches.

Not all affected applications have yet been ported from GTK3 to GTK4
(or from gtk-rs 0.18 to a more recent version). I will try to backport
the necessary changes from upstream (where available).

Applications that have not or cannot be ported (for example, because
of dead upstream projects) will need to be retired. (Alternatively,
the packages can be adapted to build with vendored Rust dependencies,
but I recommend not doing this for applications that are dead and
depend on dead libraries.)

Fabio