usage: tautline red-green-check [-h] [--project PROJECT] [--target TARGET]
                                --file FILE --test-command TEST_COMMAND
                                [--strict]

options:
  -h, --help            show this help message and exit
  --project PROJECT
  --target TARGET
  --file FILE           Source file to mutate (a changed critical-journey
                        source).
  --test-command TEST_COMMAND
                        Command (run via bash -c in --target) that should FAIL
                        when the code breaks.
  --strict              Fail closed when a mutation survives.
