Function run_audit 

pub fn run_audit(opts: &AuditOptions<'_>, gate_marker: Option<&str>) -> ExitCode

Run the full audit command: execute analyses, print results, return exit code. Run audit, optionally tagged with a gate marker (e.g. "pre-commit") so Fallow Impact can record a containment event when the gate blocks then clears. The marker only affects the local Impact store; it never changes the verdict, exit code, or output.