Refactor

Evidence-driven refactoring — where does structural improvement actually pay off, then make that change without changing behavior. Survey mode diagnoses by evidence, not aesthetics — git churn × complexity hotspots, the recurring-bug log, upcoming work — and verdicts each candidate REFACTOR/PREP/LEAVE/WATCH, where LEAVE is the default and "the textbook recommends it" is never a reason. Execute mode takes one approved candidate in small behavior-preserving moves, suite green after each. Keeps a debt register in out/refactor/tracker.md so repeat surveys open with what changed. Use for "clean up this module", "improve the architecture", "pay down tech debt" — e.g. "/refactor…