Set up the CLI application.

Long-option flag names that take a value across all subcommands. Used by the argv-normalisation step in oaspec.main to translate the GNU --name value form into glint’s expected --name=value form. Must stay in sync with the glint.string_flag(...) calls below: any new value-bearing long-option flag must be added here, otherwise the space-separated form will fail with invalid flag '<name>'.