Refactor speech recognizer, audio capture, and system routes for improved clarity and functionality

- Update `speech/recognizer.py` to handle empty queue exceptions.
- Replace `pause_event` with `_pause_event` in `audio/capture.py` for consistency.
- Cleanup and standardize formatting in `system_routes.py`.

src/voice_dialogue/api/routes/system_routes.py

@@ -219,13 +219,13 @@ async def pause_system(request: Request):
                 success=False,
                 message="系统未启动，无法暂停"
             )
-        
+
         if _system_status["status"] == "paused":
             return SystemResponse(
                 success=False,
                 message="系统已经暂停"
             )
-        
+
         if _system_status["status"] in ["starting", "stopping"]:
             return SystemResponse(
                 success=False,
@@ -294,19 +294,19 @@ async def resume_system(request: Request):
                 success=False,
                 message="系统未启动，请先启动系统"
             )
-        
+
         if _system_status["status"] == "running":
             return SystemResponse(
                 success=False,
                 message="系统已经在运行中"
             )
-        
+
         if _system_status["status"] in ["starting", "stopping"]:
             return SystemResponse(
                 success=False,
                 message="系统正在启动或停止中，请稍后再试"
             )
-        
+
         if _system_status["status"] != "paused":
             return SystemResponse(
                 success=False,
@@ -360,4 +360,4 @@ async def resume_system(request: Request):
         # 恢复状态
         if _system_status["status"] == "running":
             _system_status["status"] = "paused"
-        raise HTTPException(status_code=500, detail=f"恢复语音对话系统失败: {str(e)}")
+        raise HTTPException(status_code=500, detail=f"恢复语音对话系统失败: {str(e)}")

src/voice_dialogue/services/audio/capture.py

@@ -4,8 +4,8 @@
 """
 
 import ctypes
-import time
 import threading
+import time
 
 import numpy as np
 
@@ -24,17 +24,17 @@ class EchoCancellingAudioCapture(BaseThread):
         super().__init__(group, target, name, args, kwargs, daemon=daemon)
 
         self.audio_frames_queue = audio_frames_queue
-        self.pause_event = threading.Event()
-    
+        self._pause_event = threading.Event()
+
     @property
     def is_paused(self):
-        return self.pause_event.is_set()
+        return self._pause_event.is_set()
 
     def pause(self):
-        self.pause_event.set()
-    
+        self._pause_event.set()
+
     def resume(self):
-        self.pause_event.clear()
+        self._pause_event.clear()
 
     def run(self):
         """主运行循环，持续获取音频数据"""

src/voice_dialogue/services/speech/recognizer.py

@@ -1,6 +1,6 @@
 import time
 import typing
-from queue import Queue
+from queue import Queue, Empty
 
 import numpy as np
 
@@ -15,7 +15,7 @@ class ASRWorker(BaseThread):
     def __init__(self, group=None, target=None, name=None, args=(), kwargs=None, *, daemon=None,
                  user_voice_queue: Queue,
                  transcribed_text_queue: Queue,
-                 language: typing.Literal["auto", "zh", "en"] = "zh"):
+                 language: typing.Literal["auto", "zh", "en"]):
         super().__init__(group, target, name, args, kwargs, daemon=daemon)
 
         self.language = language
@@ -32,7 +32,11 @@ class ASRWorker(BaseThread):
         self.is_ready = True
 
         while not self.stopped():
-            voice_task: VoiceTask = self.user_voice_queue.get()
+            try:
+                voice_task: VoiceTask = self.user_voice_queue.get(block=False, timeout=0.1)
+            except Empty:
+                continue
+
             voice_task.language = self.language
             voice_task.whisper_start_time = time.time()
             user_voice: np.array = voice_task.user_voice