code-clean

Cut dead code and over-long comments from termio's Swift, verifying every deletion against a build. Knows this repo's real failure mode (essay-length doc comments, not restated-code slop) and periphery's four known false-positive shapes. Invoke when the user says 'clean dead code', 'clean up the comments', 'the comments are too long', 'remove unused code', 'tighten this file', '清理死代码', '注释太啰嗦', '精简一下注释'.