Live end-to-end surfaced a 500 on every tht call: ThtRunner prepended
'-c <config>' before the subcommand, but tht has no global -c option
('No such option: -c'). --config/-c is a per-command option, so it must be
appended AFTER the subcommand. Extracted buildArgv() and fixed the unit test
that had codified the wrong (prepended) order.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>