cs-refactor 是做什么的?
Code optimization sub-process entry, handling work with "unchanged behavior, changed structure" (structure / performance / readability), executed step by step as scan → design → apply with manual approval at each step. Trigger: when the user says "optimize this / refactor / rewrite / split this / bad performance / too long code" without any behavioral changes. Does not handle new feature requests / bugs / cross-module architecture redesigns.