This broke the builds for apps not having categories in their appstream
files.

Just like the app templates the file templates have a specific install
location.

Also the KTEMPLATESDIR is only used as a fallback, because it suggests
that all templates are in that dir, which is not true.

This is currently done on the signing machines as part of the F-Droid
nightly pipeline, but should rather happen as part of the build process
in the future.

Compared to the binary factory script this has a few extensions already:
- Besides recovering information from APKs we can now consume appdata
  files directly, or scan the entire source dir.
- Screenshots from appdata files are downloaded.
- The 'x-test' language is ignored.
- Donation and translation information are added.
- Add links to the source code repository, if we can determine that.

The result is put into a single archive per APK, so we can easily transfer
that to the signing machine via Jenkins alongside the APK.

Have the C counterpart take care of the C files and the C++ for the C++
files.
Don't forget to skip the server C implementation.

With this MR cmake gets rerun when the dirs/subdirs of the template change.

And by setting the `DEPENDS` property of the tar command to this list of the dirs/subdirs of the template we ensure that the command gets executed whenever the files change.

This matters for libraries in the same repository as the application that
also have an AAR that needs to be integrated, as well as QML plugins. For
this to work we need to consider the build directory as a search prefix,
and produce the exact directory layout there that androiddeployqt expects.

For libraries this is then almost transparent for the application build
system, the only thing that needs to be taken care of manually is putting
the corresponding -android-dependencies.xml file into the right place in
the build dir as well. A macro wrapping that might be an option to
centralize that logic here as well in the future.

For QML plugins this is transparent if you have them set up to work without
installation already anyway, otherwise that setup has to be done for this
to work.

Example: https://invent.kde.org/pim/itinerary/-/merge_requests/28

https://invent.kde.org/frameworks/knotifications/-/merge_requests/12 would
presumably also need this (not tested yet).

I had reuse installed but it wasn't being found. Now it is.

1) remove AlignTrailingComments: true

=> this avoids multiline comment changes if e.g. one longer member/variable is added with comments behind it

2) add AllowShortLambdasOnASingleLine: Empty

=> avoid the uglification of lambdas