This function:
Reads the project-level _variables.yml file
Saves it to your system-wide froggeR config directory
Prompts for confirmation if a global configuration already exists
The saved configuration is stored in rappdirs::user_config_dir('froggeR')
and will automatically be used in new froggeR projects created with
init or write_variables.
This is useful for maintaining consistent author metadata (name, email, affiliations, etc.)
across all your projects without having to re-enter it each time.