docs: def GetAllFiles(self):
      """Yields all defined source file paths.
  
      This includes file paths defined directly and those defined implicitly by
      defining a directory.
      """
      for filepath in self._files:
        yield filepath
  
      for dirpath in self._dirs:
        for filepath in ArtifactRegistrySources._GetDirYamlFiles(dirpath):
          if filepath in self._files:
            continue
          yield filepath