[bugfix] can not read the last sentence

lib/utils/tts_util.dart

@@ -17,7 +17,11 @@ class TtsUtil {
     await execute('send', {'text': text});
   }
 
-  static Future<void> stopTts() async {
+  static Future<void> complete() async {
+    await execute('complete');
+  }
+
+  static Future<void> stop() async {
     await execute('stop');
   }
 }