refactor: the Sonar remarks on the small fixes taken care of

- the log stops through a flag kept in a function, not a global one
- the messages are put together with std::format
- a vehicle dropped on a trainset in the launcher goes in once the
  trainset is drawn, so the vehicles are gone through with a plain loop
  again; the drop split into a new vehicle and a moved one
- the scenario that can't be opened is caught as the runtime error it
  is, a file name outside of the code page as the system error it is
- a track of an unknown type is left out through the pointer owning it
- the keyword of a track type written out by a function of its own
- the picked node forgotten with ranges::replace_if, the empty
  Forget_Node of the base renderer told why it is empty
- FileCased takes the path it works on

world/Track.h

@@ -358,6 +358,8 @@ private:
     void deserialize_( std::istream &Input );
     // export() subclass details, sends basic content of the class in legacy (text) format to provided stream
     void export_as_text_( std::ostream &Output ) const;
+    // the keyword the track is written with, by its type and for a plain one by what runs on it
+    char const *type_keyword() const;
     // locates specified profile in the profile database, potentially loading it from a file
     static std::pair<std::string, int> fetch_track_rail_profile( std::string const &Profile );
     // loads content of specified file and converts it into a vertex array