fix: msg_stamp.size() is unsigned,should convert to int (#2523)

TouchZZZ

2025-05-22 eccf74684743593950ad259877db7ce9ffc06e93

1
2
ID0012W0013 https://isv-data.oss-cn-hangzhou.aliyuncs.com/ics/MaaS/ASR/test_audio/asr_example_zh.wav
ID0012W0014 https://isv-data.oss-cn-hangzhou.aliyuncs.com/ics/MaaS/ASR/test_audio/asr_example_en.wav