quality pass II: rune-safe truncate, final polish

Author: jkyberneees

cmd/kode/subagent.go

@@ -448,8 +448,9 @@ func extractFilesChanged(messages []llm.Message) []string {
 }
 
 func truncate(s string, n int) string {
-	if len(s) <= n {
+	runes := []rune(s)
+	if len(runes) <= n {
 		return s
 	}
-	return s[:n] + "…"
+	return string(runes[:n]) + "…"
 }