[QuickLite] Quick App Lite configuration available for users

The Quick lite configurations should preferably be exposed and made available to users (in addition to running them on CI). Documentation is one thing, but ideally user could command the "configure" script to use a specific configuration. There does not seem to be a precedent for this kind of thing in Qt 6.

One somewhat promising option could be CMake presets, available since CMake 3.19. However one major problem is that the CMakePresets.json must be located in the same directory as the project CMakeLists.txt. This might work with top level builds though. But at any rate, as first time use case it needs to proprerly thought out and e.g. added as a configure option.