thoughtbox:refactor

Friction-gated refactoring using the Theseus protocol. Prevents scope creep and refactoring fugue state by enforcing file scope boundaries, visa-based expansion, checkpoint audits, and a brittleness counter. Use when refactoring code, restructuring modules, renaming across files, or any task where "structure changes but behavior must stay the same". Triggers on "refactor", "restructure", "rename across", "extract…