Function is_valid_rerun_severity 

pub fn is_valid_rerun_severity(severity: &str, has_category: bool) -> bool

Severities valid for a rerun filter — which differs from the report rollup, because rerun filters tasks (or their messages), it doesn’t aggregate a report (R-9). With a category the scope is over log messages (warning/error/fatal/invalid + the all-messages info); without one it is over task status (no_problem/warning/error/fatal/invalid — no_problem IS a legitimate rerun scope, e.g. regenerating output after a worker upgrade, and info is not a task status). One shared validator for the agent (rerun_report) and human (serve_rerun) surfaces, so both reject the same typos instead of silently mis-scoping to no_problem.