fix(perception): preserve quaternion alignment across binary ingress

src/k1link/perception/streaming_sensors.py

@@ -170,9 +170,18 @@ def normalized_sensor(modality: str, sequence: int, time_ns: int, raw: bytes) ->
     if modality != "pose" or len(raw) != 56:
         raise ValueError("normalized pose layout outside bound")
     values = np.frombuffer(raw, "<f8")
-    if not np.isfinite(values).all() or abs(float(np.linalg.norm(values[3:])) - 1) > 0.01:
+    # The quaternion begins at byte 24 of the wire body. On the qualified x86
+    # NumPy runtime, its 8-mod-16 address selects a different dot/norm reduction
+    # and changes two downstream ranges by one ULP. Own a tiny aligned copy,
+    # matching the archive reader's numeric layout without changing any values
+    # or the projection/norm algorithm. Covered by the cache scratch allowance.
+    quaternion = np.array(values[3:], copy=True)
+    if quaternion.ctypes.data % 16:
+        raise ValueError("unqualified quaternion numeric buffer alignment")
+    quaternion.setflags(write=False)
+    if not np.isfinite(values).all() or abs(float(np.linalg.norm(quaternion)) - 1) > 0.01:
         raise ValueError("invalid source pose")
-    return SensorEvent(time_ns, "pose", sequence, (values[:3], values[3:]))
+    return SensorEvent(time_ns, "pose", sequence, (values[:3], quaternion))
 
 
 class CausalSensorWindow: