message: fix: correct prefix stripping logic
diff: @@ -34,6 +34,7 @@ protected:
  class PythonFilesystem : public FileSystem {
  private:
  const string prefix;
  + const string name;
  const py::object filesystem;
  string stripPrefix(string input) {
  if (CanHandleFile(input)) {
  @@ -44,13 +45,13 @@ private:
  }
  public:
  - explicit PythonFilesystem(const string prefix, const py::object filesystem)
  - : prefix(prefix), filesystem(filesystem) {
  + explicit PythonFilesystem(const string name, const py::object filesystem)
  + : prefix(name + "://"), name(name), filesystem(filesystem) {
  }
  protected:
  string GetName() const {
  - return py::str(py::type::of(filesystem).attr("__name__"));
  + return name;
  }
  public:
  