The QML refactor in 1.0.4 used prefix /qml with file paths like
qml/Main.qml, embedding resources at qrc:/qml/qml/Main.qml while
main.cpp loads qrc:/qml/Main.qml. Use prefix / so paths match.
Also derive the displayed app version from CMake PROJECT_VERSION and
add a qrc_resources_test to prevent this regression in CI.
