更新雷达相位中心 CAD 先验，并放宽主机桥接后的弱相关峰 δt 门控。

Co-authored-by: Cursor <cursoragent@cursor.com>

imu_lidar/time_offset.py

@@ -137,8 +137,16 @@ def estimate_time_offset(
         f"LiDAR mean pair rotation {np.mean([rotation_angle_deg(r) for r in rotations]):.2f} deg"
     )
     notes.append(f"searched delta_t in ±{search_s:.3f}s by direct correlation")
-    ok = peak > 0.15
-    if not ok:
+    # Host-UTC-bridged sessions are already on one timeline; |ω| peak can stay
+    # weak even at the correct lag (ICP rate vs gyro scale). Accept near-zero δt.
+    near_zero = abs(float(delta)) <= min(0.05, 0.25 * float(search_s))
+    ok = peak > 0.15 or near_zero
+    if peak <= 0.15 and near_zero:
+        notes.append(
+            f"correlation peak weak ({peak:.3f}) but |delta_t|={abs(delta):.4f}s ~0; "
+            "accepting as already-aligned (e.g. host UTC bridge)"
+        )
+    elif not ok:
         notes.append("correlation peak is weak; check overlapping motion and axis units")
     return TimeOffsetResult(
         delta_t_s=delta,