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

utilities/utilities.h

@@ -219,7 +219,7 @@ template <> bool extract_value(bool &Variable, std::string const &Key, std::stri
 bool FileExists(std::string const &Filename);
 // the file as it's named on the disk when only the case of its name differs, as in the sceneries made on Windows; empty when
 // there's none. the folders have to be named in their case; on Windows, finding the names in any case itself, the file given or none
-std::string FileCased(std::string const &Filename);
+std::string FileCased(std::filesystem::path const &Filename);
 
 std::pair<std::string, std::string> FileExists(std::vector<std::string> const &Names, std::vector<std::string> const &Extensions);