root: recreate the qml engine on reload instead of clearing it

This causes singletons to be recreated instead of kept alive.

src/main.cpp

@@ -1,5 +1,3 @@
 #include "core/main.hpp"
 
-int main(int argc, char** argv) {
-	return qs_main(argc, argv);
-}
+int main(int argc, char** argv) { return qs_main(argc, argv); }