Cleanup pass 2

AGENTS.md

@@ -68,6 +68,7 @@ Run these (in order) before declaring a change done:
 ```bash
 rm -rf .next            # only if you moved/renamed routes or layouts
 npx tsc --noEmit        # type check
+npm run knip            # unused files / exports (local; no remote CI)
 npx vitest run          # unit + component (~185 test files)
 npx next build          # production build + route manifest
 ```