surgical-changeslisted

# Surgical Changes Solve the requested problem completely, with no unrelated improvement hidden in the diff. Smallest coherent change means the narrowest correct change, not the fewest edited lines or a patch over the symptom. ## Set the boundary Before editing, identify: - the observable bug or requested outcome; - the symbols, tests, and boundary that must change; - the behavior that must remain unchanged. Classify each contemplated edit: 1. **Required** - directly fixes or implements the request. 2. **Coupled** - needed so the required change compiles, remains correct, or can be tested at the nearest meaningful boundary. 3. **Adjacent** - useful cleanup or another defect, but not causally necessary. Only required and coupled edits belong in the diff. If you cannot explain why a hunk is needed for the request, leave it out. ## Change only what the cause requires - Follow local names, control flow, error style, types, and test idioms, even when you would choose differently in new code. - Fix the root cause within the established boundary. Do not duplicate policy or add a brittle special case merely to minimize line count. - Preserve public call-shape, defaults, return values, failure semantics, effect order, and serialization unless the request requires changing them. - Do not rename or move neighboring code, reformat untouched regions, introduce an abstraction or dependency, tighten unrelated types, or rewrite nearby errors opportunistically. - Do not mix feature w