add stream raw frame access

example/python/example.py

@@ -33,14 +33,17 @@ def demo_streaming(dev: EskinDevice, duration_sec: float = 5.0):
 
     # 线程安全的队列（参考 ROS demo 的 read_loop + publish_callback 分离模式）
     queue: deque = deque(maxlen=100)
+    raw_queue: deque = deque(maxlen=100)
     running = True
 
     def read_loop():
-        """独立读取线程：持续从设备读取 sample"""
+        """独立读取线程：持续从设备读取 sample 和原始帧"""
         while running:
             try:
                 sample = dev.read_sample(timeout_ms=50)
                 queue.append(sample)
+                raw_frame = dev.read_stream_frame(timeout_ms=1)
+                raw_queue.append(raw_frame)
             except RuntimeError:
                 # 超时等非致命错误，继续读取
                 pass
@@ -55,12 +58,14 @@ def demo_streaming(dev: EskinDevice, duration_sec: float = 5.0):
     while time.monotonic() - start < duration_sec:
         if queue:
             sample: CFingerSample = queue.popleft()
+            raw_frame = raw_queue.popleft() if raw_queue else b""
             f = sample.combined_force.force
             mod = sample.combined_force.module
             print(
                 f"[{sample.sequence:5d}] "
                 f"module={mod}  "
-                f"fx={f.fx}  fy={f.fy}  fz={f.fz}"
+                f"fx={f.fx}  fy={f.fy}  fz={f.fz}  "
+                f"raw_len={len(raw_frame)}"
             )
             count += 1
         else:
@@ -89,4 +94,4 @@ def main():
 
 
 if __name__ == "__main__":
-    main()
+    main()