fix: 按复位请求目标确认参考版本并隔离复位状态

防止在途旧帧提前触发归零，并保留旧 reset 用法。SDK 101 项针对性回归与 lint 通过。

tests/test_force_session.py

@@ -155,6 +155,33 @@ def collect_baseline(session, source, *, start=1, count=30, reference_id="ref-1"
     ]
 
 
+def test_external_zero_waits_for_the_requested_target_reference_version():
+    source = FakeMeasurementSource(raw_for=lambda _: (10.0, 20.0, 30.0))
+    session = make_session(source)
+    session.request_zero_external_reset(
+        reference_id="second-reset", declared_unloaded=True, target_reference_version=2
+    )
+    outputs = []
+    for frame_id, version in enumerate([0, 1, 1, 2, 2]):
+        row = source.read_measurement_frame(None, frame_id=frame_id)
+        outputs.append(session.process_measurement(row, stamp(frame_id), tracker_reset_seq=version))
+    assert [o.measurement.zero.phase for o in outputs] == [
+        "resetting", "resetting", "resetting", "collecting", "collecting"
+    ]
+    assert outputs[-1].measurement.zero.collected_frames == 2
+    assert outputs[-1].measurement.zero.first_frame_id == 3
+
+
+@pytest.mark.parametrize("target", [0, -1, True])
+def test_external_zero_rejects_invalid_target_reference_version(target):
+    session = make_session(FakeMeasurementSource())
+    with pytest.raises(ValueError, match="target_reference_version"):
+        session.request_zero_external_reset(
+            reference_id="invalid-target", declared_unloaded=True,
+            target_reference_version=target,
+        )
+
+
 # ---------------------------------------------------------------------------
 # T1: executable fake chain, one model call, cached reads, missing is not zero
 # ---------------------------------------------------------------------------
@@ -1210,3 +1237,39 @@ def test_old_readout_entry_keeps_filter_then_convert_order() -> None:
     # is exactly the recorded historical behaviour.
     assert outputs[-1] == pytest.approx(4.0)
     assert readout.raw_unfiltered == (250.0, 0.0, 0.0)
+
+
+def test_readout_reset_halves_clear_only_their_own_state() -> None:
+    """The flow EMA is image-side state; the readout history is force-side state."""
+    from orisys.force_readout import ForceReadout
+
+    flow = np.zeros((2, 2, 2), dtype=np.float32)
+
+    readout = ForceReadout({"flow_ema_alpha": 0.5, "force_median_window": 3},
+                           config_fps=30.0)
+    readout.apply_flow_ema(flow)
+    readout.apply((10.0, 1.0, 2.0))
+    filtered = readout.filtered_raw
+    raw_unfiltered = readout.raw_unfiltered
+    unfiltered_newton = readout.unfiltered_newton
+
+    readout.reset_flow_ema()
+    assert readout._ema_flow is None
+    # The force-side history survives a reset that only rebases the image stage.
+    assert readout.filtered_raw == filtered
+    assert readout.raw_unfiltered == raw_unfiltered
+    assert readout.unfiltered_newton == unfiltered_newton
+
+    readout = ForceReadout({"flow_ema_alpha": 0.5, "force_median_window": 3},
+                           config_fps=30.0)
+    readout.apply_flow_ema(flow)
+    readout.apply((10.0, 1.0, 2.0))
+    readout.reset_readout()
+    assert readout._ema_flow is not None
+    assert readout.filtered_raw is None
+    assert readout.raw_unfiltered is None
+    assert readout.unfiltered_newton is None
+
+    readout.reset()
+    assert readout._ema_flow is None
+    assert readout.filtered_raw is None