Increase audio capture chunk size to 1024 in `capture.py` for smoother streaming

src/voice_dialogue/services/audio/capture.py

@@ -77,7 +77,7 @@ class AudioCapture(BaseThread):
         此方法不提供回声消除或语音活动检测。
         """
         p = pyaudio.PyAudio()
-        chunk = 512
+        chunk = 1024
         sample_rate = 16000
         stream = p.open(
             format=pyaudio.paInt16,