After a quick shot, the changes look well to me. Tested on native Windows and built fine.
If required, I can try to add the mingw meson build in CI and replace autotools with meson also.
Not sure if the Meson is already ready to be used for CI. Ideally, the CI builds generate full installers in release quality. Maybe it would be better to first port Geany-Plugins to Meson?
A few concerns: - is it possible to build Geany-Plugins with Autotools against a Geany built with Meson? - the Meson build installs the docs into the root prefix instead of `share/doc/geany` - the Meson build does not install libexec/geany/geany-run-helper.bat (for full details find the lift of installed files by Autotools and Meson attached) [tree_at.txt](https://github.com/geany/geany/files/11301612/tree_at.txt) [tree_meson.txt](https://github.com/geany/geany/files/11301613/tree_meson.txt)