code: @PostMapping("/addMappingProject")
    public String addMappingProject(
        @RequestParam("mapping-project-name") String name,
        @RequestParam("target-entity") String targetEntity,
        @RequestParam("depth") int depth) {
      MappingProject newMappingProject = mappingService.addMappingProject(name, targetEntity, depth);
      return "redirect:"
          + getMappingServiceMenuUrl()
          + "/mappingproject/"
          + newMappingProject.getIdentifier();
    }
docs: Adds a new mapping project.
  
  @param name name of the mapping project
  @param targetEntity name of the project's first {@link MappingTarget}'s target entity
  @return redirect URL for the newly created mapping project