Skladnik kdereview checklist

Background:
While Skladnik, by the former name KSokoban, is some old KDE software added in 1998 (Git repo conversion: 401d3537, or original SVN: https://phabricator.kde.org/R883:10132) and was released for all of KDE 1 - KDE 3, it fell behind in the port to Qt4/KDELibs4, since only ported bit by bit by different people all the last 15 years, to work even with Qt6/KF6 now, yet so far not returned to also being released, despite working as before since years. To be changed now.

• If from outside KDE, has completed the Incubator process Not relevant
• The REUSE Specification - Version 3.0 is applied when stating licenses and when adding license files to a project. Each source file either must contain SPDX identifiers or license headers to state under which terms the software may be used, modified and redistributed. See Licensing Policy
• Passing CI job for Reuse linting Old KDE project, so exempted here
• A Messages.sh file which extracts all the i18n() translations
• A metainfo.xml file (previously appdata.xml) with AppStream data AppStream Guidelines
• A screenshot in product-screenshots
• Check the code with some sanity tools like clazy or clang-tidy, if not already done as part of CI runs.
• Documentation appropriate to the project: if a library, API documentation (such as Doxygen for C++), if an application, user documentation (such as a README detailing what the application does or is for, how to install/build, and other such useful information)
• A bugs.kde.org product
• Passing Gitlab CI build jobs
• Passing KDE neon build
• App packages in Flatpak, Snap, AppImages and Windows etc as appropriate