mod/decide-strictest collects every proven rule (pl-query-all) and applies the
harshest action by mod/action-severity (keep<escalate<hide<remove<ban), an
alternative to the engine's first-match precedence. Diverges from first-match
exactly when rule order and severity disagree. Same decision shape + :strategy;
engine untouched. Own suite. +14 tests.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>